Merge of the code for partitioned key cache (mwl#85) into 5.2.

36 files changed, 8240 insertions, 333 deletions

diff --git a/include/keycache.h b/include/keycache.h
index 8c4ee4afe81..25a204cede2 100644
--- a/include/keycache.h
+++ b/include/keycache.h
@@ -19,96 +19,156 @@
 #define _keycache_h
 C_MODE_START
 
-/* declare structures that is used by st_key_cache */
 
-struct st_block_link;
-typedef struct st_block_link BLOCK_LINK;
-struct st_keycache_page;
-typedef struct st_keycache_page KEYCACHE_PAGE;
-struct st_hash_link;
-typedef struct st_hash_link HASH_LINK;
 
-/* info about requests in a waiting queue */
-typedef struct st_keycache_wqueue
-{
-  struct st_my_thread_var *last_thread;  /* circular list of waiting threads */
-} KEYCACHE_WQUEUE;
+/* 
+  Currently the default key cache is created as non-partitioned at 
+  the start of the server unless the server is started with the parameter 
+  --key-cache-partitions that is greater than 0
+*/
+
+#define DEFAULT_KEY_CACHE_PARTITIONS    0
+
+/* 
+  MAX_KEY_CACHE_PARTITIONS cannot be greater than 
+  sizeof(MYISAM_SHARE::dirty_part_map)
+  Currently sizeof(MYISAM_SHARE::dirty_part_map)=sizeof(ulonglong)
+*/
 
-#define CHANGED_BLOCKS_HASH 128             /* must be power of 2 */
+#define MAX_KEY_CACHE_PARTITIONS    64
+
+/* The structure to get statistical data about a key cache */
+
+typedef struct st_key_cache_statistics
+{
+  ulonglong mem_size;       /* memory for cache buffers/auxiliary structures */
+  ulonglong block_size;     /* size of the each buffers in the key cache     */
+  ulonglong blocks_used;    /* maximum number of used blocks/buffers         */ 
+  ulonglong blocks_unused;  /* number of currently unused blocks             */
+  ulonglong blocks_changed; /* number of currently dirty blocks              */
+  ulonglong read_requests;  /* number of read requests (read hits)           */
+  ulonglong reads;        /* number of actual reads from files into buffers  */
+  ulonglong write_requests; /* number of write requests (write hits)         */
+  ulonglong writes;       /* number of actual writes from buffers into files */
+} KEY_CACHE_STATISTICS;
+
+#define NUM_LONG_KEY_CACHE_STAT_VARIABLES 3
+
+/* The type of a key cache object */
+typedef enum key_cache_type
+{
+  SIMPLE_KEY_CACHE,         
+  PARTITIONED_KEY_CACHE
+} KEY_CACHE_TYPE;
+
+
+typedef
+  int    (*INIT_KEY_CACHE)  
+           (void *, uint key_cache_block_size,
+            size_t use_mem, uint division_limit, uint age_threshold);
+typedef
+  int    (*RESIZE_KEY_CACHE)
+           (void *, uint key_cache_block_size,
+            size_t use_mem, uint division_limit, uint age_threshold);
+typedef
+  void   (*CHANGE_KEY_CACHE_PARAM)
+           (void *keycache_cb,
+            uint division_limit, uint age_threshold);
+typedef
+  uchar* (*KEY_CACHE_READ)
+           (void *keycache_cb,
+            File file, my_off_t filepos, int level,
+            uchar *buff, uint length,
+            uint block_length, int return_buffer);
+typedef
+  int    (*KEY_CACHE_INSERT)
+           (void *keycache_cb,
+            File file, my_off_t filepos, int level,
+            uchar *buff, uint length);
+typedef
+  int    (*KEY_CACHE_WRITE)
+           (void *keycache_cb,
+            File file, void *file_extra,
+            my_off_t filepos, int level,
+            uchar *buff, uint length, 
+            uint block_length, int force_write);
+typedef
+  int    (*FLUSH_KEY_BLOCKS)
+           (void *keycache_cb,
+            int file, void *file_extra,
+            enum flush_type type); 
+typedef
+  int    (*RESET_KEY_CACHE_COUNTERS)
+           (const char *name, void *keycache_cb); 
+typedef
+  void   (*END_KEY_CACHE)
+           (void *keycache_cb, my_bool cleanup);
+typedef
+  void   (*GET_KEY_CACHE_STATISTICS)
+           (void *keycache_cb, uint partition_no, 
+            KEY_CACHE_STATISTICS *key_cache_stats); 
+typedef
+  ulonglong (*GET_KEY_CACHE_STAT_VALUE)
+              (void *keycache_cb, uint var_no); 
 
 /*
-  The key cache structure
-  It also contains read-only statistics parameters.
+  An object of the type KEY_CACHE_FUNCS contains pointers to all functions
+  from the key cache interface.
+  Currently a key cache can be of two types: simple and partitioned.
+  For each of them its own static structure of the type KEY_CACHE_FUNCS is
+  defined . The structures contain the pointers to the implementations of
+  the interface functions used by simple key caches and partitioned key
+  caches respectively. Pointers to these structures are assigned to key cache
+  objects at the time of their creation.
 */   
 
+typedef struct st_key_cache_funcs 
+{
+  INIT_KEY_CACHE init;
+  RESIZE_KEY_CACHE         resize;
+  CHANGE_KEY_CACHE_PARAM   change_param;     
+  KEY_CACHE_READ           read;
+  KEY_CACHE_INSERT         insert;
+  KEY_CACHE_WRITE          write;
+  FLUSH_KEY_BLOCKS         flush;
+  RESET_KEY_CACHE_COUNTERS reset_counters; 
+  END_KEY_CACHE            end;
+  GET_KEY_CACHE_STATISTICS get_stats; 
+  GET_KEY_CACHE_STAT_VALUE get_stat_val;
+} KEY_CACHE_FUNCS;
+
+
 typedef struct st_key_cache
 {
-  my_bool key_cache_inited;
-  my_bool in_resize;             /* true during resize operation             */
-  my_bool resize_in_flush;       /* true during flush of resize operation    */
+  KEY_CACHE_TYPE key_cache_type; /* type of the key cache used for debugging */
+  void *keycache_cb;             /* control block of the used key cache      */
+  KEY_CACHE_FUNCS *interface_funcs; /* interface functions of the key cache  */
+  ulonglong param_buff_size;     /* size the memory allocated for the cache  */
+  ulong param_block_size;        /* size of the blocks in the key cache      */
+  ulong param_division_limit;    /* min. percentage of warm blocks           */
+  ulong param_age_threshold;     /* determines when hot block is downgraded  */
+  ulong param_partitions;        /* number of the key cache partitions       */
+  my_bool key_cache_inited;      /* <=> key cache has been created           */
   my_bool can_be_used;           /* usage of cache for read/write is allowed */
-  size_t key_cache_mem_size;      /* specified size of the cache memory       */
-  uint key_cache_block_size;     /* size of the page buffer of a cache block */
-  ulong min_warm_blocks;         /* min number of warm blocks;               */
-  ulong age_threshold;           /* age threshold for hot blocks             */
-  ulonglong keycache_time;       /* total number of block link operations    */
-  uint hash_entries;             /* max number of entries in the hash table  */
-  int hash_links;                /* max number of hash links                 */
-  int hash_links_used;           /* number of hash links currently used      */
-  int disk_blocks;               /* max number of blocks in the cache        */
-  ulong blocks_used; /* maximum number of concurrently used blocks */
-  ulong blocks_unused; /* number of currently unused blocks */
-  ulong blocks_changed;          /* number of currently dirty blocks         */
-  ulong warm_blocks;             /* number of blocks in warm sub-chain       */
-  ulong cnt_for_resize_op;       /* counter to block resize operation        */
-  long blocks_available;      /* number of blocks available in the LRU chain */
-  HASH_LINK **hash_root;         /* arr. of entries into hash table buckets  */
-  HASH_LINK *hash_link_root;     /* memory for hash table links              */
-  HASH_LINK *free_hash_list;     /* list of free hash links                  */
-  BLOCK_LINK *free_block_list;   /* list of free blocks */
-  BLOCK_LINK *block_root;        /* memory for block links                   */
-  uchar HUGE_PTR *block_mem;     /* memory for block buffers                 */
-  BLOCK_LINK *used_last;         /* ptr to the last block of the LRU chain   */
-  BLOCK_LINK *used_ins;          /* ptr to the insertion block in LRU chain  */
-  pthread_mutex_t cache_lock;    /* to lock access to the cache structure    */
-  KEYCACHE_WQUEUE resize_queue;  /* threads waiting during resize operation  */
-  /*
-    Waiting for a zero resize count. Using a queue for symmetry though
-    only one thread can wait here.
-  */
-  KEYCACHE_WQUEUE waiting_for_resize_cnt;
-  KEYCACHE_WQUEUE waiting_for_hash_link; /* waiting for a free hash link     */
-  KEYCACHE_WQUEUE waiting_for_block;    /* requests waiting for a free block */
-  BLOCK_LINK *changed_blocks[CHANGED_BLOCKS_HASH]; /* hash for dirty file bl.*/
-  BLOCK_LINK *file_blocks[CHANGED_BLOCKS_HASH];    /* hash for other file bl.*/
-
-  /*
-    The following variables are and variables used to hold parameters for
-    initializing the key cache.
-  */
-
-  ulonglong param_buff_size;    /* size the memory allocated for the cache  */
-  ulong param_block_size;       /* size of the blocks in the key cache      */
-  ulong param_division_limit;   /* min. percentage of warm blocks           */
-  ulong param_age_threshold;    /* determines when hot block is downgraded  */
-
-  /* Statistics variables. These are reset in reset_key_cache_counters(). */
-  ulong global_blocks_changed;	/* number of currently dirty blocks         */
+  my_bool in_init;		 /* Set to 1 in MySQL during init/resize     */
+  uint partitions;               /* actual number of partitions              */
+  size_t key_cache_mem_size;     /* specified size of the cache memory       */
+  ulong blocks_used;           /* maximum number of concurrently used blocks */
+  ulong blocks_unused;           /* number of currently unused blocks        */
+  ulong global_blocks_changed;	 /* number of currently dirty blocks         */
   ulonglong global_cache_w_requests;/* number of write requests (write hits) */
   ulonglong global_cache_write;     /* number of writes from cache to files  */
   ulonglong global_cache_r_requests;/* number of read requests (read hits)   */
   ulonglong global_cache_read;      /* number of reads from files to cache   */
-
-  int blocks;                   /* max number of blocks in the cache        */
-  my_bool in_init;		/* Set to 1 in MySQL during init/resize     */
 } KEY_CACHE;
 
+
 /* The default key cache */
 extern KEY_CACHE dflt_key_cache_var, *dflt_key_cache;
 
 extern int init_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
 			  size_t use_mem, uint division_limit,
-			  uint age_threshold);
+			  uint age_threshold, uint partitions);
 extern int resize_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
 			    size_t use_mem, uint division_limit,
 			    uint age_threshold);
@@ -122,12 +182,18 @@ extern int key_cache_insert(KEY_CACHE *keycache,
                             File file, my_off_t filepos, int level,
                             uchar *buff, uint length);
 extern int key_cache_write(KEY_CACHE *keycache,
-                           File file, my_off_t filepos, int level,
+                           File file, void *file_extra,
+                           my_off_t filepos, int level,
                            uchar *buff, uint length,
-			   uint block_length,int force_write);
+			   uint block_length, int force_write);
 extern int flush_key_blocks(KEY_CACHE *keycache,
-                            int file, enum flush_type type);
+                            int file, void *file_extra,
+                            enum flush_type type);
 extern void end_key_cache(KEY_CACHE *keycache, my_bool cleanup);
+extern void get_key_cache_statistics(KEY_CACHE *keycache,
+                                     uint partition_no, 
+                                     KEY_CACHE_STATISTICS *key_cache_stats);
+extern ulonglong get_key_cache_stat_value(KEY_CACHE *keycache, uint var_no);
 
 /* Functions to handle multiple key caches */
 extern my_bool multi_keycache_init(void);
@@ -140,5 +206,11 @@ extern void multi_key_cache_change(KEY_CACHE *old_data,
 				   KEY_CACHE *new_data);
 extern int reset_key_cache_counters(const char *name,
                                     KEY_CACHE *key_cache);
+extern int repartition_key_cache(KEY_CACHE *keycache,
+                                 uint key_cache_block_size,
+			         size_t use_mem, 
+                                 uint division_limit,
+			         uint age_threshold,
+                                 uint partitions);
 C_MODE_END
 #endif /* _keycache_h */
diff --git a/mysql-test/r/information_schema.result b/mysql-test/r/information_schema.result
index e49885f9118..9e126c5e49e 100644
--- a/mysql-test/r/information_schema.result
+++ b/mysql-test/r/information_schema.result
@@ -69,6 +69,7 @@ INNODB_LOCK_WAITS
 INNODB_RSEG
 INNODB_TABLE_STATS
 INNODB_TRX
+KEY_CACHES
 KEY_COLUMN_USAGE
 PARTITIONS
 PLUGINS
diff --git a/mysql-test/r/information_schema_all_engines.result b/mysql-test/r/information_schema_all_engines.result
index c91d9fcbe38..3f80d5c43e5 100644
--- a/mysql-test/r/information_schema_all_engines.result
+++ b/mysql-test/r/information_schema_all_engines.result
@@ -13,6 +13,7 @@ FILES
 GLOBAL_STATUS
 GLOBAL_VARIABLES
 INDEX_STATISTICS
+KEY_CACHES
 KEY_COLUMN_USAGE
 PARTITIONS
 PLUGINS
@@ -76,6 +77,7 @@ FILES	TABLE_SCHEMA
 GLOBAL_STATUS	VARIABLE_NAME
 GLOBAL_VARIABLES	VARIABLE_NAME
 INDEX_STATISTICS	TABLE_SCHEMA
+KEY_CACHES	KEY_CACHE_NAME
 KEY_COLUMN_USAGE	CONSTRAINT_SCHEMA
 PARTITIONS	TABLE_SCHEMA
 PLUGINS	PLUGIN_NAME
@@ -139,6 +141,7 @@ FILES	TABLE_SCHEMA
 GLOBAL_STATUS	VARIABLE_NAME
 GLOBAL_VARIABLES	VARIABLE_NAME
 INDEX_STATISTICS	TABLE_SCHEMA
+KEY_CACHES	KEY_CACHE_NAME
 KEY_COLUMN_USAGE	CONSTRAINT_SCHEMA
 PARTITIONS	TABLE_SCHEMA
 PLUGINS	PLUGIN_NAME
@@ -221,6 +224,7 @@ INNODB_LOCK_WAITS	information_schema.INNODB_LOCK_WAITS	1
 INNODB_RSEG	information_schema.INNODB_RSEG	1
 INNODB_TABLE_STATS	information_schema.INNODB_TABLE_STATS	1
 INNODB_TRX	information_schema.INNODB_TRX	1
+KEY_CACHES	information_schema.KEY_CACHES	1
 KEY_COLUMN_USAGE	information_schema.KEY_COLUMN_USAGE	1
 PARTITIONS	information_schema.PARTITIONS	1
 PBXT_STATISTICS	information_schema.PBXT_STATISTICS	1
@@ -259,6 +263,7 @@ Database: information_schema
 | GLOBAL_STATUS                         |
 | GLOBAL_VARIABLES                      |
 | INDEX_STATISTICS                      |
+| KEY_CACHES                            |
 | KEY_COLUMN_USAGE                      |
 | PARTITIONS                            |
 | PLUGINS                               |
@@ -312,6 +317,7 @@ Database: INFORMATION_SCHEMA
 | GLOBAL_STATUS                         |
 | GLOBAL_VARIABLES                      |
 | INDEX_STATISTICS                      |
+| KEY_CACHES                            |
 | KEY_COLUMN_USAGE                      |
 | PARTITIONS                            |
 | PLUGINS                               |
@@ -357,5 +363,5 @@ Wildcard: inf_rmation_schema
 +--------------------+
 SELECT table_schema, count(*) FROM information_schema.TABLES WHERE table_schema IN ('mysql', 'INFORMATION_SCHEMA', 'test', 'mysqltest') AND table_name<>'ndb_binlog_index' AND table_name<>'ndb_apply_status' GROUP BY TABLE_SCHEMA;
 table_schema	count(*)
-information_schema	48
+information_schema	49
 mysql	22
diff --git a/mysql-test/r/key_cache.result b/mysql-test/r/key_cache.result
index 08d8059f61b..cd1518baec6 100644
--- a/mysql-test/r/key_cache.result
+++ b/mysql-test/r/key_cache.result
@@ -1,5 +1,7 @@
 drop table if exists t1, t2, t3;
-SET @save_key_buffer=@@key_buffer_size;
+SET @save_key_buffer_size=@@key_buffer_size;
+SET @save_key_cache_block_size=@@key_cache_block_size;
+SET @save_key_cache_partitions=@@key_cache_partitions;
 SELECT @@key_buffer_size, @@small.key_buffer_size;
 @@key_buffer_size	@@small.key_buffer_size
 2097152	131072
@@ -37,7 +39,7 @@ SELECT @@small.key_buffer_size;
 SELECT @@medium.key_buffer_size;
 @@medium.key_buffer_size
 0
-SET @@global.key_buffer_size=@save_key_buffer;
+SET @@global.key_buffer_size=@save_key_buffer_size;
 SELECT @@default.key_buffer_size;
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'default.key_buffer_size' at line 1
 SELECT @@skr.storage_engine="test";
@@ -366,3 +368,432 @@ Variable_name	Value
 key_cache_block_size	1536
 SET GLOBAL key_cache_block_size= @bug28478_key_cache_block_size;
 DROP TABLE t1;
+set global key_buffer_size=@save_key_buffer_size;
+set global key_cache_block_size=@save_key_cache_block_size;
+select @@key_buffer_size;
+@@key_buffer_size
+2097152
+select @@key_cache_block_size;
+@@key_cache_block_size
+1024
+select @@key_cache_partitions;
+@@key_cache_partitions
+0
+create table t1 (
+p int not null auto_increment primary key,
+a char(10));
+create table t2 (
+p int  not null auto_increment primary key,
+i int, a char(10), key k1(i), key k2(a));
+select @@key_cache_partitions;
+@@key_cache_partitions
+0
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	NULL	NULL	2097152	1024	0	#	0	0	0	0	0
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+insert into t1 values (1, 'qqqq'), (2, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+(3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+p	a
+1	qqqq
+2	yyyy
+select * from t2;
+p	i	a
+1	1	qqqq
+2	1	pppp
+3	1	yyyy
+4	3	zzzz
+update t1 set p=3 where p=1;
+update t2 set i=2 where i=1;
+show status like 'key_%';
+Variable_name	Value
+Key_blocks_not_flushed	0
+Key_blocks_unused	KEY_BLOCKS_UNUSED
+Key_blocks_used	4
+Key_read_requests	22
+Key_reads	0
+Key_write_requests	26
+Key_writes	6
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	NULL	NULL	2097152	1024	4	#	0	22	0	26	6
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+delete from t2 where a='zzzz';
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	NULL	NULL	2097152	1024	4	#	0	29	0	32	9
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+delete from t1;
+delete from t2;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	NULL	NULL	2097152	1024	4	#	0	29	0	32	9
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+set global key_cache_partitions=2;
+select @@key_cache_partitions;
+@@key_cache_partitions
+2
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	2097152	1024	0	#	0	0	0	0	0
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+insert into t1 values (1, 'qqqq'), (2, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+(3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+p	a
+1	qqqq
+2	yyyy
+select * from t2;
+p	i	a
+1	1	qqqq
+2	1	pppp
+3	1	yyyy
+4	3	zzzz
+update t1 set p=3 where p=1;
+update t2 set i=2 where i=1;
+show status like 'key_%';
+Variable_name	Value
+Key_blocks_not_flushed	0
+Key_blocks_unused	KEY_BLOCKS_UNUSED
+Key_blocks_used	4
+Key_read_requests	22
+Key_reads	0
+Key_write_requests	26
+Key_writes	6
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	2097152	1024	4	#	0	22	0	26	6
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+delete from t1;
+delete from t2;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	2097152	1024	4	#	0	22	0	26	6
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+set global key_cache_partitions=1;
+select @@key_cache_partitions;
+@@key_cache_partitions
+1
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	1	NULL	2097152	1024	0	#	0	0	0	0	0
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+insert into t1 values (1, 'qqqq'), (2, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+(3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+p	a
+1	qqqq
+2	yyyy
+select * from t2;
+p	i	a
+1	1	qqqq
+2	1	pppp
+3	1	yyyy
+4	3	zzzz
+update t1 set p=3 where p=1;
+update t2 set i=2 where i=1;
+show status like 'key_%';
+Variable_name	Value
+Key_blocks_not_flushed	0
+Key_blocks_unused	KEY_BLOCKS_UNUSED
+Key_blocks_used	4
+Key_read_requests	22
+Key_reads	0
+Key_write_requests	26
+Key_writes	6
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	1	NULL	2097152	1024	4	#	0	22	0	26	6
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+delete from t1;
+delete from t2;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	1	NULL	2097152	1024	4	#	0	22	0	26	6
+small	NULL	NULL	1048576	1024	1	#	0	1	0	2	1
+flush tables;
+flush status;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	1	NULL	2097152	1024	4	#	0	0	0	0	0
+small	NULL	NULL	1048576	1024	1	#	0	0	0	0	0
+set global key_buffer_size=32*1024;
+select @@key_buffer_size;
+@@key_buffer_size
+32768
+set global key_cache_partitions=2;
+select @@key_cache_partitions;
+@@key_cache_partitions
+2
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	0	#	0	0	0	0	0
+small	NULL	NULL	1048576	1024	1	#	0	0	0	0	0
+insert into t1 values (1, 'qqqq'), (2, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+(3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+p	a
+1	qqqq
+2	yyyy
+select * from t2;
+p	i	a
+1	1	qqqq
+2	1	pppp
+3	1	yyyy
+4	3	zzzz
+update t1 set p=3 where p=1;
+update t2 set i=2 where i=1;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	4	#	0	22	0	26	6
+small	NULL	NULL	1048576	1024	1	#	0	0	0	0	0
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	6733	#	3684	103
+small	NULL	NULL	1048576	1024	#	#	0	0	#	0	0
+select * from t1 where p between 1010 and 1020 ;
+p	a
+select * from t2 where p between 1010 and 1020 ;
+p	i	a
+1010	2	pppp
+1011	2	yyyy
+1012	3	zzzz
+1013	2	qqqq
+1014	2	pppp
+1015	2	yyyy
+1016	3	zzzz
+1017	2	qqqq
+1018	2	pppp
+1019	2	yyyy
+1020	3	zzzz
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	6750	#	3684	103
+small	NULL	NULL	1048576	1024	#	#	0	0	#	0	0
+flush tables;
+flush status;
+update t1 set a='zzzz' where a='qqqq';
+update t2 set i=1 where i=2;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3076	18	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+set global keycache1.key_buffer_size=256*1024;
+select @@keycache1.key_buffer_size;
+@@keycache1.key_buffer_size
+262144
+set global keycache1.key_cache_partitions=7;
+select @@keycache1.key_cache_partitions;
+@@keycache1.key_cache_partitions
+7
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3076	18	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	7	NULL	262143	2048	#	#	0	0	0	0	0
+select * from information_schema.key_caches where key_cache_name like "key%"
+                                                  and partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+keycache1	7	NULL	262143	2048	0	#	0	0	0	0	0
+cache index t1 key (`primary`) in keycache1;
+Table	Op	Msg_type	Msg_text
+test.t1	assign_to_keycache	status	OK
+explain select p from t1 where p between 1010 and 1020;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	4	NULL	1	Using where; Using index
+select p from t1 where p between 1010 and 1020;
+p
+explain select i from t2 where p between 1010 and 1020;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	PRIMARY	PRIMARY	4	NULL	28	Using where
+select i from t2 where p between 1010 and 1020;
+i
+1
+1
+3
+1
+1
+1
+3
+1
+1
+1
+3
+explain select count(*) from t1, t2 where t1.p = t2.i;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	k1	k1	5	NULL	1024	Using index
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.i	1	Using index
+select count(*) from t1, t2 where t1.p = t2.i;
+count(*)
+256
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	7	NULL	262143	2048	#	#	0	14	3	0	0
+select * from information_schema.key_caches where key_cache_name like "key%"
+                                                  and partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+keycache1	7	NULL	262143	2048	3	#	0	14	3	0	0
+cache index t2 in keycache1;
+Table	Op	Msg_type	Msg_text
+test.t2	assign_to_keycache	status	OK
+update t2 set p=p+3000, i=2 where a='qqqq';
+select * from information_schema.key_caches where key_cache_name like "key%"
+                                                  and partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+keycache1	7	NULL	262143	2048	25	#	0	2082	25	1071	19
+set global keycache2.key_buffer_size=1024*1024;
+cache index t2 in keycache2;
+Table	Op	Msg_type	Msg_text
+test.t2	assign_to_keycache	status	OK
+insert into t2 values (2000, 3, 'yyyy');
+select * from information_schema.key_caches where key_cache_name like "keycache2"
+                                                  and partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+keycache2	NULL	NULL	1048576	1024	6	#	0	6	6	3	3
+select * from information_schema.key_caches where key_cache_name like "key%" 
+and partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+keycache1	7	NULL	262143	2048	25	#	0	2082	25	1071	19
+keycache2	NULL	NULL	1048576	1024	6	#	0	6	6	3	3
+cache index t2 in keycache1;
+Table	Op	Msg_type	Msg_text
+test.t2	assign_to_keycache	status	OK
+update t2 set p=p+5000 where a='zzzz';
+select * from t2 where p between 1010 and 1020;
+p	i	a
+1010	1	pppp
+1011	1	yyyy
+1014	1	pppp
+1015	1	yyyy
+1018	1	pppp
+1019	1	yyyy
+explain select p from t2  where p between 1010 and 1020;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	PRIMARY	PRIMARY	4	NULL	7	Using where; Using index
+select p from t2 where p between 1010 and 1020;
+p
+1010
+1011
+1014
+1015
+1018
+1019
+explain select i from t2 where a='yyyy' and i=3;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	k1,k2	k1	5	const	188	Using where
+select i from t2 where a='yyyy' and i=3;
+i
+3
+explain select a from t2 where a='yyyy' and i=3;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	k1,k2	k1	5	const	188	Using where
+select a from t2 where a='yyyy' and i=3 ;
+a
+yyyy
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	7	NULL	262143	2048	#	#	0	3201	43	1594	30
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_cache_block_size=2*1024;
+insert into t2 values (7000, 3, 'yyyy');
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	7	NULL	262143	2048	#	#	0	6	6	3	3
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_cache_block_size=8*1024;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	3	NULL	262143	8192	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+insert into t2 values (8000, 3, 'yyyy');
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	3	NULL	262143	8192	#	#	0	6	5	3	3
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_buffer_size=64*1024;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_cache_block_size=2*1024;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	3	NULL	65535	2048	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_cache_block_size=8*1024;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_buffer_size=0;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_cache_block_size=8*1024;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_buffer_size=0;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_buffer_size=128*1024;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	1	NULL	131072	8192	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+set global keycache1.key_cache_block_size=1024;
+select * from information_schema.key_caches where partition_number is null;
+KEY_CACHE_NAME	PARTITIONS	PARTITION_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
+default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
+small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
+keycache1	7	NULL	131068	1024	#	#	0	0	0	0	0
+keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
+drop table t1,t2;
+set global keycache1.key_buffer_size=0;
+set global keycache2.key_buffer_size=0;
+set global key_buffer_size=@save_key_buffer_size;
+set global key_cache_partitions=@save_key_cache_partitions;
diff --git a/mysql-test/r/select_pkeycache.result b/mysql-test/r/select_pkeycache.result
new file mode 100644
index 00000000000..f5f9f24c898
--- /dev/null
+++ b/mysql-test/r/select_pkeycache.result
@@ -0,0 +1,4784 @@
+drop table if exists t1,t2,t3,t4,t11;
+drop table if exists t1_1,t1_2,t9_1,t9_2,t1aa,t2aa;
+drop view if exists v1;
+CREATE TABLE t1 (
+Period smallint(4) unsigned zerofill DEFAULT '0000' NOT NULL,
+Varor_period smallint(4) unsigned DEFAULT '0' NOT NULL
+);
+INSERT INTO t1 VALUES (9410,9412);
+select period from t1;
+period
+9410
+select * from t1;
+Period	Varor_period
+9410	9412
+select t1.* from t1;
+Period	Varor_period
+9410	9412
+CREATE TABLE t2 (
+auto int not null auto_increment,
+fld1 int(6) unsigned zerofill DEFAULT '000000' NOT NULL,
+companynr tinyint(2) unsigned zerofill DEFAULT '00' NOT NULL,
+fld3 char(30) DEFAULT '' NOT NULL,
+fld4 char(35) DEFAULT '' NOT NULL,
+fld5 char(35) DEFAULT '' NOT NULL,
+fld6 char(4) DEFAULT '' NOT NULL,
+UNIQUE fld1 (fld1),
+KEY fld3 (fld3),
+PRIMARY KEY (auto)
+);
+select t2.fld3 from t2 where companynr = 58 and fld3 like "%imaginable%";
+fld3
+imaginable
+select fld3 from t2 where fld3 like "%cultivation" ;
+fld3
+cultivation
+select t2.fld3,companynr from t2 where companynr = 57+1 order by fld3;
+fld3	companynr
+concoct	58
+druggists	58
+engrossing	58
+Eurydice	58
+exclaimers	58
+ferociousness	58
+hopelessness	58
+Huey	58
+imaginable	58
+judges	58
+merging	58
+ostrich	58
+peering	58
+Phelps	58
+presumes	58
+Ruth	58
+sentences	58
+Shylock	58
+straggled	58
+synergy	58
+thanking	58
+tying	58
+unlocks	58
+select fld3,companynr from t2 where companynr = 58 order by fld3;
+fld3	companynr
+concoct	58
+druggists	58
+engrossing	58
+Eurydice	58
+exclaimers	58
+ferociousness	58
+hopelessness	58
+Huey	58
+imaginable	58
+judges	58
+merging	58
+ostrich	58
+peering	58
+Phelps	58
+presumes	58
+Ruth	58
+sentences	58
+Shylock	58
+straggled	58
+synergy	58
+thanking	58
+tying	58
+unlocks	58
+select fld3 from t2 order by fld3 desc limit 10;
+fld3
+youthfulness
+yelped
+Wotan
+workers
+Witt
+witchcraft
+Winsett
+Willy
+willed
+wildcats
+select fld3 from t2 order by fld3 desc limit 5;
+fld3
+youthfulness
+yelped
+Wotan
+workers
+Witt
+select fld3 from t2 order by fld3 desc limit 5,5;
+fld3
+witchcraft
+Winsett
+Willy
+willed
+wildcats
+select t2.fld3 from t2 where fld3 = 'honeysuckle';
+fld3
+honeysuckle
+select t2.fld3 from t2 where fld3 LIKE 'honeysuckl_';
+fld3
+honeysuckle
+select t2.fld3 from t2 where fld3 LIKE 'hon_ysuckl_';
+fld3
+honeysuckle
+select t2.fld3 from t2 where fld3 LIKE 'honeysuckle%';
+fld3
+honeysuckle
+select t2.fld3 from t2 where fld3 LIKE 'h%le';
+fld3
+honeysuckle
+select t2.fld3 from t2 where fld3 LIKE 'honeysuckle_';
+fld3
+select t2.fld3 from t2 where fld3 LIKE 'don_t_find_me_please%';
+fld3
+explain select t2.fld3 from t2 where fld3 = 'honeysuckle';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	fld3	fld3	30	const	1	Using where; Using index
+explain select fld3 from t2 ignore index (fld3) where fld3 = 'honeysuckle';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
+explain select fld3 from t2 use index (fld1) where fld3 = 'honeysuckle';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
+explain select fld3 from t2 use index (fld3) where fld3 = 'honeysuckle';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	fld3	fld3	30	const	1	Using where; Using index
+explain select fld3 from t2 use index (fld1,fld3) where fld3 = 'honeysuckle';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	fld3	fld3	30	const	1	Using where; Using index
+explain select fld3 from t2 ignore index (fld3,not_used);
+ERROR 42000: Key 'not_used' doesn't exist in table 't2'
+explain select fld3 from t2 use index (not_used);
+ERROR 42000: Key 'not_used' doesn't exist in table 't2'
+select t2.fld3 from t2 where fld3 >= 'honeysuckle' and fld3 <= 'honoring' order by fld3;
+fld3
+honeysuckle
+honoring
+explain select t2.fld3 from t2 where fld3 >= 'honeysuckle' and fld3 <= 'honoring' order by fld3;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	fld3	fld3	30	NULL	2	Using where; Using index
+select fld1,fld3 from t2 where fld3="Colombo" or fld3 = "nondecreasing" order by fld3;
+fld1	fld3
+148504	Colombo
+068305	Colombo
+000000	nondecreasing
+select fld1,fld3 from t2 where companynr = 37 and fld3 = 'appendixes';
+fld1	fld3
+232605	appendixes
+1232605	appendixes
+1232606	appendixes
+1232607	appendixes
+1232608	appendixes
+1232609	appendixes
+select fld1 from t2 where fld1=250501 or fld1="250502";
+fld1
+250501
+250502
+explain select fld1 from t2 where fld1=250501 or fld1="250502";
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	fld1	fld1	4	NULL	2	Using where; Using index
+select fld1 from t2 where fld1=250501 or fld1=250502 or fld1 >= 250505 and fld1 <= 250601 or fld1 between 250501 and 250502;
+fld1
+250501
+250502
+250505
+250601
+explain select fld1 from t2 where fld1=250501 or fld1=250502 or fld1 >= 250505 and fld1 <= 250601 or fld1 between 250501 and 250502;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	fld1	fld1	4	NULL	4	Using where; Using index
+select fld1,fld3 from t2 where companynr = 37 and fld3 like 'f%';
+fld1	fld3
+218401	faithful
+018007	fanatic
+228311	fated
+018017	featherweight
+218022	feed
+088303	feminine
+058004	Fenton
+038017	fetched
+018054	fetters
+208101	fiftieth
+238007	filial
+013606	fingerings
+218008	finishers
+038205	firearm
+188505	fitting
+202301	Fitzpatrick
+238008	fixedly
+012001	flanking
+018103	flint
+018104	flopping
+188007	flurried
+013602	foldout
+226205	foothill
+232102	forgivably
+228306	forthcoming
+186002	freakish
+208113	freest
+231315	freezes
+036002	funereal
+226209	furnishings
+198006	furthermore
+select fld3 from t2 where fld3 like "L%" and fld3 = "ok";
+fld3
+select fld3 from t2 where (fld3 like "C%" and fld3 = "Chantilly");
+fld3
+Chantilly
+select fld1,fld3 from t2 where fld1 like "25050%";
+fld1	fld3
+250501	poisoning
+250502	Iraqis
+250503	heaving
+250504	population
+250505	bomb
+select fld1,fld3 from t2 where fld1 like "25050_";
+fld1	fld3
+250501	poisoning
+250502	Iraqis
+250503	heaving
+250504	population
+250505	bomb
+select distinct companynr from t2;
+companynr
+00
+37
+36
+50
+58
+29
+40
+53
+65
+41
+34
+68
+select distinct companynr from t2 order by companynr;
+companynr
+00
+29
+34
+36
+37
+40
+41
+50
+53
+58
+65
+68
+select distinct companynr from t2 order by companynr desc;
+companynr
+68
+65
+58
+53
+50
+41
+40
+37
+36
+34
+29
+00
+select distinct t2.fld3,period from t2,t1 where companynr=37 and fld3 like "O%";
+fld3	period
+obliterates	9410
+offload	9410
+opaquely	9410
+organizer	9410
+overestimating	9410
+overlay	9410
+select distinct fld3 from t2 where companynr = 34 order by fld3;
+fld3
+absentee
+accessed
+ahead
+alphabetic
+Asiaticizations
+attitude
+aye
+bankruptcies
+belays
+Blythe
+bomb
+boulevard
+bulldozes
+cannot
+caressing
+charcoal
+checksumming
+chess
+clubroom
+colorful
+cosy
+creator
+crying
+Darius
+diffusing
+duality
+Eiffel
+Epiphany
+Ernestine
+explorers
+exterminated
+famine
+forked
+Gershwins
+heaving
+Hodges
+Iraqis
+Italianization
+Lagos
+landslide
+libretto
+Majorca
+mastering
+narrowed
+occurred
+offerers
+Palestine
+Peruvianizes
+pharmaceutic
+poisoning
+population
+Pygmalion
+rats
+realest
+recording
+regimented
+retransmitting
+reviver
+rouses
+scars
+sicker
+sleepwalk
+stopped
+sugars
+translatable
+uncles
+unexpected
+uprisings
+versatility
+vest
+select distinct fld3 from t2 limit 10;
+fld3
+abates
+abiding
+Abraham
+abrogating
+absentee
+abut
+accessed
+accruing
+accumulating
+accuracies
+select distinct fld3 from t2 having fld3 like "A%" limit 10;
+fld3
+abates
+abiding
+Abraham
+abrogating
+absentee
+abut
+accessed
+accruing
+accumulating
+accuracies
+select distinct substring(fld3,1,3) from t2 where fld3 like "A%";
+substring(fld3,1,3)
+aba
+abi
+Abr
+abs
+abu
+acc
+acq
+acu
+Ade
+adj
+Adl
+adm
+Ado
+ads
+adv
+aer
+aff
+afi
+afl
+afo
+agi
+ahe
+aim
+air
+Ald
+alg
+ali
+all
+alp
+alr
+ama
+ame
+amm
+ana
+and
+ane
+Ang
+ani
+Ann
+Ant
+api
+app
+aqu
+Ara
+arc
+Arm
+arr
+Art
+Asi
+ask
+asp
+ass
+ast
+att
+aud
+Aug
+aut
+ave
+avo
+awe
+aye
+Azt
+select distinct substring(fld3,1,3) as a from t2 having a like "A%" order by a limit 10;
+a
+aba
+abi
+Abr
+abs
+abu
+acc
+acq
+acu
+Ade
+adj
+select distinct substring(fld3,1,3) from t2 where fld3 like "A%" limit 10;
+substring(fld3,1,3)
+aba
+abi
+Abr
+abs
+abu
+acc
+acq
+acu
+Ade
+adj
+select distinct substring(fld3,1,3) as a from t2 having a like "A%" limit 10;
+a
+aba
+abi
+Abr
+abs
+abu
+acc
+acq
+acu
+Ade
+adj
+create table t3 (
+period    int not null,
+name      char(32) not null,
+companynr int not null,
+price     double(11,0),
+price2     double(11,0),
+key (period),
+key (name)
+);
+create temporary table tmp engine = myisam select * from t3;
+insert into t3 select * from tmp;
+insert into tmp select * from t3;
+insert into t3 select * from tmp;
+insert into tmp select * from t3;
+insert into t3 select * from tmp;
+insert into tmp select * from t3;
+insert into t3 select * from tmp;
+insert into tmp select * from t3;
+insert into t3 select * from tmp;
+insert into tmp select * from t3;
+insert into t3 select * from tmp;
+insert into tmp select * from t3;
+insert into t3 select * from tmp;
+insert into tmp select * from t3;
+insert into t3 select * from tmp;
+insert into tmp select * from t3;
+insert into t3 select * from tmp;
+alter table t3 add t2nr int not null auto_increment primary key first;
+drop table tmp;
+SET SQL_BIG_TABLES=1;
+select distinct concat(fld3," ",fld3) as namn from t2,t3 where t2.fld1=t3.t2nr order by namn limit 10;
+namn
+Abraham Abraham
+abrogating abrogating
+admonishing admonishing
+Adolph Adolph
+afield afield
+aging aging
+ammonium ammonium
+analyzable analyzable
+animals animals
+animized animized
+SET SQL_BIG_TABLES=0;
+select distinct concat(fld3," ",fld3) from t2,t3 where t2.fld1=t3.t2nr order by fld3 limit 10;
+concat(fld3," ",fld3)
+Abraham Abraham
+abrogating abrogating
+admonishing admonishing
+Adolph Adolph
+afield afield
+aging aging
+ammonium ammonium
+analyzable analyzable
+animals animals
+animized animized
+select distinct fld5 from t2 limit 10;
+fld5
+neat
+Steinberg
+jarring
+tinily
+balled
+persist
+attainments
+fanatic
+measures
+rightfulness
+select distinct fld3,count(*) from t2 group by companynr,fld3 limit 10;
+fld3	count(*)
+affixed	1
+and	1
+annoyers	1
+Anthony	1
+assayed	1
+assurers	1
+attendants	1
+bedlam	1
+bedpost	1
+boasted	1
+SET SQL_BIG_TABLES=1;
+select distinct fld3,count(*) from t2 group by companynr,fld3 limit 10;
+fld3	count(*)
+affixed	1
+and	1
+annoyers	1
+Anthony	1
+assayed	1
+assurers	1
+attendants	1
+bedlam	1
+bedpost	1
+boasted	1
+SET SQL_BIG_TABLES=0;
+select distinct fld3,repeat("a",length(fld3)),count(*) from t2 group by companynr,fld3 limit 100,10;
+fld3	repeat("a",length(fld3))	count(*)
+circus	aaaaaa	1
+cited	aaaaa	1
+Colombo	aaaaaaa	1
+congresswoman	aaaaaaaaaaaaa	1
+contrition	aaaaaaaaaa	1
+corny	aaaaa	1
+cultivation	aaaaaaaaaaa	1
+definiteness	aaaaaaaaaaaa	1
+demultiplex	aaaaaaaaaaa	1
+disappointing	aaaaaaaaaaaaa	1
+select distinct companynr,rtrim(space(512+companynr)) from t3 order by 1,2;
+companynr	rtrim(space(512+companynr))
+37	
+78	
+101	
+154	
+311	
+447	
+512	
+select distinct fld3 from t2,t3 where t2.companynr = 34 and t2.fld1=t3.t2nr order by fld3;
+fld3
+explain select t3.t2nr,fld3 from t2,t3 where t2.companynr = 34 and t2.fld1=t3.t2nr order by t3.t2nr,fld3;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	fld1	NULL	NULL	NULL	1199	Using where; Using temporary; Using filesort
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.fld1	1	Using where; Using index
+explain select * from t3 as t1,t3 where t1.period=t3.period order by t3.period;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	period	NULL	NULL	NULL	41810	Using temporary; Using filesort
+1	SIMPLE	t3	ref	period	period	4	test.t1.period	4181	
+explain select * from t3 as t1,t3 where t1.period=t3.period order by t3.period limit 10;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t3	index	period	period	4	NULL	1	
+1	SIMPLE	t1	ref	period	period	4	test.t3.period	4181	
+explain select * from t3 as t1,t3 where t1.period=t3.period order by t1.period limit 10;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	index	period	period	4	NULL	1	
+1	SIMPLE	t3	ref	period	period	4	test.t1.period	4181	
+select period from t1;
+period
+9410
+select period from t1 where period=1900;
+period
+select fld3,period from t1,t2 where fld1 = 011401 order by period;
+fld3	period
+breaking	9410
+select fld3,period from t2,t3 where t2.fld1 = 011401 and t2.fld1=t3.t2nr and t3.period=1001;
+fld3	period
+breaking	1001
+explain select fld3,period from t2,t3 where t2.fld1 = 011401 and t3.t2nr=t2.fld1 and 1001 = t3.period;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	const	fld1	fld1	4	const	1	
+1	SIMPLE	t3	const	PRIMARY,period	PRIMARY	4	const	1	
+select fld3,period from t2,t1 where companynr*10 = 37*10;
+fld3	period
+breaking	9410
+Romans	9410
+intercepted	9410
+bewilderingly	9410
+astound	9410
+admonishing	9410
+sumac	9410
+flanking	9410
+combed	9410
+subjective	9410
+scatterbrain	9410
+Eulerian	9410
+Kane	9410
+overlay	9410
+perturb	9410
+goblins	9410
+annihilates	9410
+Wotan	9410
+snatching	9410
+concludes	9410
+laterally	9410
+yelped	9410
+grazing	9410
+Baird	9410
+celery	9410
+misunderstander	9410
+handgun	9410
+foldout	9410
+mystic	9410
+succumbed	9410
+Nabisco	9410
+fingerings	9410
+aging	9410
+afield	9410
+ammonium	9410
+boat	9410
+intelligibility	9410
+Augustine	9410
+teethe	9410
+dreaded	9410
+scholastics	9410
+audiology	9410
+wallet	9410
+parters	9410
+eschew	9410
+quitter	9410
+neat	9410
+Steinberg	9410
+jarring	9410
+tinily	9410
+balled	9410
+persist	9410
+attainments	9410
+fanatic	9410
+measures	9410
+rightfulness	9410
+capably	9410
+impulsive	9410
+starlet	9410
+terminators	9410
+untying	9410
+announces	9410
+featherweight	9410
+pessimist	9410
+daughter	9410
+decliner	9410
+lawgiver	9410
+stated	9410
+readable	9410
+attrition	9410
+cascade	9410
+motors	9410
+interrogate	9410
+pests	9410
+stairway	9410
+dopers	9410
+testicle	9410
+Parsifal	9410
+leavings	9410
+postulation	9410
+squeaking	9410
+contrasted	9410
+leftover	9410
+whiteners	9410
+erases	9410
+Punjab	9410
+Merritt	9410
+Quixotism	9410
+sweetish	9410
+dogging	9410
+scornfully	9410
+bellow	9410
+bills	9410
+cupboard	9410
+sureties	9410
+puddings	9410
+fetters	9410
+bivalves	9410
+incurring	9410
+Adolph	9410
+pithed	9410
+Miles	9410
+trimmings	9410
+tragedies	9410
+skulking	9410
+flint	9410
+flopping	9410
+relaxing	9410
+offload	9410
+suites	9410
+lists	9410
+animized	9410
+multilayer	9410
+standardizes	9410
+Judas	9410
+vacuuming	9410
+dentally	9410
+humanness	9410
+inch	9410
+Weissmuller	9410
+irresponsibly	9410
+luckily	9410
+culled	9410
+medical	9410
+bloodbath	9410
+subschema	9410
+animals	9410
+Micronesia	9410
+repetitions	9410
+Antares	9410
+ventilate	9410
+pityingly	9410
+interdependent	9410
+Graves	9410
+neonatal	9410
+chafe	9410
+honoring	9410
+realtor	9410
+elite	9410
+funereal	9410
+abrogating	9410
+sorters	9410
+Conley	9410
+lectured	9410
+Abraham	9410
+Hawaii	9410
+cage	9410
+hushes	9410
+Simla	9410
+reporters	9410
+Dutchman	9410
+descendants	9410
+groupings	9410
+dissociate	9410
+coexist	9410
+Beebe	9410
+Taoism	9410
+Connally	9410
+fetched	9410
+checkpoints	9410
+rusting	9410
+galling	9410
+obliterates	9410
+traitor	9410
+resumes	9410
+analyzable	9410
+terminator	9410
+gritty	9410
+firearm	9410
+minima	9410
+Selfridge	9410
+disable	9410
+witchcraft	9410
+betroth	9410
+Manhattanize	9410
+imprint	9410
+peeked	9410
+swelling	9410
+interrelationships	9410
+riser	9410
+Gandhian	9410
+peacock	9410
+bee	9410
+kanji	9410
+dental	9410
+scarf	9410
+chasm	9410
+insolence	9410
+syndicate	9410
+alike	9410
+imperial	9410
+convulsion	9410
+railway	9410
+validate	9410
+normalizes	9410
+comprehensive	9410
+chewing	9410
+denizen	9410
+schemer	9410
+chronicle	9410
+Kline	9410
+Anatole	9410
+partridges	9410
+brunch	9410
+recruited	9410
+dimensions	9410
+Chicana	9410
+announced	9410
+praised	9410
+employing	9410
+linear	9410
+quagmire	9410
+western	9410
+relishing	9410
+serving	9410
+scheduling	9410
+lore	9410
+eventful	9410
+arteriole	9410
+disentangle	9410
+cured	9410
+Fenton	9410
+avoidable	9410
+drains	9410
+detectably	9410
+husky	9410
+impelling	9410
+undoes	9410
+evened	9410
+squeezes	9410
+destroyer	9410
+rudeness	9410
+beaner	9410
+boorish	9410
+Everhart	9410
+encompass	9410
+mushrooms	9410
+Alison	9410
+externally	9410
+pellagra	9410
+cult	9410
+creek	9410
+Huffman	9410
+Majorca	9410
+governing	9410
+gadfly	9410
+reassigned	9410
+intentness	9410
+craziness	9410
+psychic	9410
+squabbled	9410
+burlesque	9410
+capped	9410
+extracted	9410
+DiMaggio	9410
+exclamation	9410
+subdirectory	9410
+Gothicism	9410
+feminine	9410
+metaphysically	9410
+sanding	9410
+Miltonism	9410
+freakish	9410
+index	9410
+straight	9410
+flurried	9410
+denotative	9410
+coming	9410
+commencements	9410
+gentleman	9410
+gifted	9410
+Shanghais	9410
+sportswriting	9410
+sloping	9410
+navies	9410
+leaflet	9410
+shooter	9410
+Joplin	9410
+babies	9410
+assails	9410
+admiring	9410
+swaying	9410
+Goldstine	9410
+fitting	9410
+Norwalk	9410
+analogy	9410
+deludes	9410
+cokes	9410
+Clayton	9410
+exhausts	9410
+causality	9410
+sating	9410
+icon	9410
+throttles	9410
+communicants	9410
+dehydrate	9410
+priceless	9410
+publicly	9410
+incidentals	9410
+commonplace	9410
+mumbles	9410
+furthermore	9410
+cautioned	9410
+parametrized	9410
+registration	9410
+sadly	9410
+positioning	9410
+babysitting	9410
+eternal	9410
+hoarder	9410
+congregates	9410
+rains	9410
+workers	9410
+sags	9410
+unplug	9410
+garage	9410
+boulder	9410
+specifics	9410
+Teresa	9410
+Winsett	9410
+convenient	9410
+buckboards	9410
+amenities	9410
+resplendent	9410
+sews	9410
+participated	9410
+Simon	9410
+certificates	9410
+Fitzpatrick	9410
+Evanston	9410
+misted	9410
+textures	9410
+save	9410
+count	9410
+rightful	9410
+chaperone	9410
+Lizzy	9410
+clenched	9410
+effortlessly	9410
+accessed	9410
+beaters	9410
+Hornblower	9410
+vests	9410
+indulgences	9410
+infallibly	9410
+unwilling	9410
+excrete	9410
+spools	9410
+crunches	9410
+overestimating	9410
+ineffective	9410
+humiliation	9410
+sophomore	9410
+star	9410
+rifles	9410
+dialysis	9410
+arriving	9410
+indulge	9410
+clockers	9410
+languages	9410
+Antarctica	9410
+percentage	9410
+ceiling	9410
+specification	9410
+regimented	9410
+ciphers	9410
+pictures	9410
+serpents	9410
+allot	9410
+realized	9410
+mayoral	9410
+opaquely	9410
+hostess	9410
+fiftieth	9410
+incorrectly	9410
+decomposition	9410
+stranglings	9410
+mixture	9410
+electroencephalography	9410
+similarities	9410
+charges	9410
+freest	9410
+Greenberg	9410
+tinting	9410
+expelled	9410
+warm	9410
+smoothed	9410
+deductions	9410
+Romano	9410
+bitterroot	9410
+corset	9410
+securing	9410
+environing	9410
+cute	9410
+Crays	9410
+heiress	9410
+inform	9410
+avenge	9410
+universals	9410
+Kinsey	9410
+ravines	9410
+bestseller	9410
+equilibrium	9410
+extents	9410
+relatively	9410
+pressure	9410
+critiques	9410
+befouled	9410
+rightfully	9410
+mechanizing	9410
+Latinizes	9410
+timesharing	9410
+Aden	9410
+embassies	9410
+males	9410
+shapelessly	9410
+mastering	9410
+Newtonian	9410
+finishers	9410
+abates	9410
+teem	9410
+kiting	9410
+stodgy	9410
+feed	9410
+guitars	9410
+airships	9410
+store	9410
+denounces	9410
+Pyle	9410
+Saxony	9410
+serializations	9410
+Peruvian	9410
+taxonomically	9410
+kingdom	9410
+stint	9410
+Sault	9410
+faithful	9410
+Ganymede	9410
+tidiness	9410
+gainful	9410
+contrary	9410
+Tipperary	9410
+tropics	9410
+theorizers	9410
+renew	9410
+already	9410
+terminal	9410
+Hegelian	9410
+hypothesizer	9410
+warningly	9410
+journalizing	9410
+nested	9410
+Lars	9410
+saplings	9410
+foothill	9410
+labeled	9410
+imperiously	9410
+reporters	9410
+furnishings	9410
+precipitable	9410
+discounts	9410
+excises	9410
+Stalin	9410
+despot	9410
+ripeness	9410
+Arabia	9410
+unruly	9410
+mournfulness	9410
+boom	9410
+slaughter	9410
+Sabine	9410
+handy	9410
+rural	9410
+organizer	9410
+shipyard	9410
+civics	9410
+inaccuracy	9410
+rules	9410
+juveniles	9410
+comprised	9410
+investigations	9410
+stabilizes	9410
+seminaries	9410
+Hunter	9410
+sporty	9410
+test	9410
+weasels	9410
+CERN	9410
+tempering	9410
+afore	9410
+Galatean	9410
+techniques	9410
+error	9410
+veranda	9410
+severely	9410
+Cassites	9410
+forthcoming	9410
+guides	9410
+vanish	9410
+lied	9410
+sawtooth	9410
+fated	9410
+gradually	9410
+widens	9410
+preclude	9410
+evenhandedly	9410
+percentage	9410
+disobedience	9410
+humility	9410
+gleaning	9410
+petted	9410
+bloater	9410
+minion	9410
+marginal	9410
+apiary	9410
+measures	9410
+precaution	9410
+repelled	9410
+primary	9410
+coverings	9410
+Artemia	9410
+navigate	9410
+spatial	9410
+Gurkha	9410
+meanwhile	9410
+Melinda	9410
+Butterfield	9410
+Aldrich	9410
+previewing	9410
+glut	9410
+unaffected	9410
+inmate	9410
+mineral	9410
+impending	9410
+meditation	9410
+ideas	9410
+miniaturizes	9410
+lewdly	9410
+title	9410
+youthfulness	9410
+creak	9410
+Chippewa	9410
+clamored	9410
+freezes	9410
+forgivably	9410
+reduce	9410
+McGovern	9410
+Nazis	9410
+epistle	9410
+socializes	9410
+conceptions	9410
+Kevin	9410
+uncovering	9410
+chews	9410
+appendixes	9410
+appendixes	9410
+appendixes	9410
+appendixes	9410
+appendixes	9410
+appendixes	9410
+raining	9410
+infest	9410
+compartment	9410
+minting	9410
+ducks	9410
+roped	9410
+waltz	9410
+Lillian	9410
+repressions	9410
+chillingly	9410
+noncritical	9410
+lithograph	9410
+spongers	9410
+parenthood	9410
+posed	9410
+instruments	9410
+filial	9410
+fixedly	9410
+relives	9410
+Pandora	9410
+watering	9410
+ungrateful	9410
+secures	9410
+poison	9410
+dusted	9410
+encompasses	9410
+presentation	9410
+Kantian	9410
+select fld3,period,price,price2 from t2,t3 where t2.fld1=t3.t2nr and period >= 1001 and period <= 1002 and t2.companynr = 37 order by fld3,period, price;
+fld3	period	price	price2
+admonishing	1002	28357832	8723648
+analyzable	1002	28357832	8723648
+annihilates	1001	5987435	234724
+Antares	1002	28357832	8723648
+astound	1001	5987435	234724
+audiology	1001	5987435	234724
+Augustine	1002	28357832	8723648
+Baird	1002	28357832	8723648
+bewilderingly	1001	5987435	234724
+breaking	1001	5987435	234724
+Conley	1001	5987435	234724
+dentally	1002	28357832	8723648
+dissociate	1002	28357832	8723648
+elite	1001	5987435	234724
+eschew	1001	5987435	234724
+Eulerian	1001	5987435	234724
+flanking	1001	5987435	234724
+foldout	1002	28357832	8723648
+funereal	1002	28357832	8723648
+galling	1002	28357832	8723648
+Graves	1001	5987435	234724
+grazing	1001	5987435	234724
+groupings	1001	5987435	234724
+handgun	1001	5987435	234724
+humility	1002	28357832	8723648
+impulsive	1002	28357832	8723648
+inch	1001	5987435	234724
+intelligibility	1001	5987435	234724
+jarring	1001	5987435	234724
+lawgiver	1001	5987435	234724
+lectured	1002	28357832	8723648
+Merritt	1002	28357832	8723648
+neonatal	1001	5987435	234724
+offload	1002	28357832	8723648
+parters	1002	28357832	8723648
+pityingly	1002	28357832	8723648
+puddings	1002	28357832	8723648
+Punjab	1001	5987435	234724
+quitter	1002	28357832	8723648
+realtor	1001	5987435	234724
+relaxing	1001	5987435	234724
+repetitions	1001	5987435	234724
+resumes	1001	5987435	234724
+Romans	1002	28357832	8723648
+rusting	1001	5987435	234724
+scholastics	1001	5987435	234724
+skulking	1002	28357832	8723648
+stated	1002	28357832	8723648
+suites	1002	28357832	8723648
+sureties	1001	5987435	234724
+testicle	1002	28357832	8723648
+tinily	1002	28357832	8723648
+tragedies	1001	5987435	234724
+trimmings	1001	5987435	234724
+vacuuming	1001	5987435	234724
+ventilate	1001	5987435	234724
+wallet	1001	5987435	234724
+Weissmuller	1002	28357832	8723648
+Wotan	1002	28357832	8723648
+select t2.fld1,fld3,period,price,price2 from t2,t3 where t2.fld1>= 18201 and t2.fld1 <= 18811 and t2.fld1=t3.t2nr and period = 1001 and t2.companynr = 37;
+fld1	fld3	period	price	price2
+018201	relaxing	1001	5987435	234724
+018601	vacuuming	1001	5987435	234724
+018801	inch	1001	5987435	234724
+018811	repetitions	1001	5987435	234724
+create table t4 (
+companynr tinyint(2) unsigned zerofill NOT NULL default '00',
+companyname char(30) NOT NULL default '',
+PRIMARY KEY (companynr),
+UNIQUE KEY companyname(companyname)
+) ENGINE=MyISAM MAX_ROWS=50 PACK_KEYS=1 COMMENT='companynames';
+select STRAIGHT_JOIN t2.companynr,companyname from t4,t2 where t2.companynr=t4.companynr group by t2.companynr;
+companynr	companyname
+00	Unknown
+29	company 1
+34	company 2
+36	company 3
+37	company 4
+40	company 5
+41	company 6
+50	company 11
+53	company 7
+58	company 8
+65	company 9
+68	company 10
+select SQL_SMALL_RESULT t2.companynr,companyname from t4,t2 where t2.companynr=t4.companynr group by t2.companynr;
+companynr	companyname
+00	Unknown
+29	company 1
+34	company 2
+36	company 3
+37	company 4
+40	company 5
+41	company 6
+50	company 11
+53	company 7
+58	company 8
+65	company 9
+68	company 10
+select * from t1,t1 t12;
+Period	Varor_period	Period	Varor_period
+9410	9412	9410	9412
+select t2.fld1,t22.fld1 from t2,t2 t22 where t2.fld1 >= 250501 and t2.fld1 <= 250505 and t22.fld1 >= 250501 and t22.fld1 <= 250505;
+fld1	fld1
+250501	250501
+250502	250501
+250503	250501
+250504	250501
+250505	250501
+250501	250502
+250502	250502
+250503	250502
+250504	250502
+250505	250502
+250501	250503
+250502	250503
+250503	250503
+250504	250503
+250505	250503
+250501	250504
+250502	250504
+250503	250504
+250504	250504
+250505	250504
+250501	250505
+250502	250505
+250503	250505
+250504	250505
+250505	250505
+insert into t2 (fld1, companynr) values (999999,99);
+select t2.companynr,companyname from t2 left join t4 using (companynr) where t4.companynr is null;
+companynr	companyname
+99	NULL
+select count(*) from t2 left join t4 using (companynr) where t4.companynr is not null;
+count(*)
+1199
+explain select t2.companynr,companyname from t2 left join t4 using (companynr) where t4.companynr is null;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1200	
+1	SIMPLE	t4	eq_ref	PRIMARY	PRIMARY	1	test.t2.companynr	1	Using where; Not exists
+explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr is null;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1200	Using where; Not exists
+select companynr,companyname from t2 left join t4 using (companynr) where companynr is null;
+companynr	companyname
+select count(*) from t2 left join t4 using (companynr) where companynr is not null;
+count(*)
+1200
+explain select companynr,companyname from t2 left join t4 using (companynr) where companynr is null;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
+explain select companynr,companyname from t4 left join t2 using (companynr) where companynr is null;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
+delete from t2 where fld1=999999;
+explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
+1	SIMPLE	t4	eq_ref	PRIMARY	PRIMARY	1	test.t2.companynr	1	
+explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0 or t2.companynr < 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
+1	SIMPLE	t4	eq_ref	PRIMARY	PRIMARY	1	test.t2.companynr	1	
+explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0 and t4.companynr > 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
+1	SIMPLE	t4	eq_ref	PRIMARY	PRIMARY	1	test.t2.companynr	1	
+explain select companynr,companyname from t4 left join t2 using (companynr) where companynr > 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	PRIMARY	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	
+explain select companynr,companyname from t4 left join t2 using (companynr) where companynr > 0 or companynr < 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	PRIMARY	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	
+explain select companynr,companyname from t4 left join t2 using (companynr) where companynr > 0 and companynr > 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	PRIMARY	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	
+explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0 or t2.companynr is null;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
+explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0 or t2.companynr < 0 or t4.companynr > 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	PRIMARY	NULL	NULL	NULL	12	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
+explain select t2.companynr,companyname from t4 left join t2 using (companynr) where ifnull(t2.companynr,1)>0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
+explain select companynr,companyname from t4 left join t2 using (companynr) where companynr > 0 or companynr is null;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	PRIMARY	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	
+explain select companynr,companyname from t4 left join t2 using (companynr) where companynr > 0 or companynr < 0 or companynr > 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	PRIMARY	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	
+explain select companynr,companyname from t4 left join t2 using (companynr) where ifnull(companynr,1)>0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	
+select distinct t2.companynr,t4.companynr from t2,t4 where t2.companynr=t4.companynr+1;
+companynr	companynr
+37	36
+41	40
+explain select distinct t2.companynr,t4.companynr from t2,t4 where t2.companynr=t4.companynr+1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t4	index	NULL	PRIMARY	1	NULL	12	Using index; Using temporary
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where; Using join buffer
+select t2.fld1,t2.companynr,fld3,period from t3,t2 where t2.fld1 = 38208 and t2.fld1=t3.t2nr and period = 1008 or t2.fld1 = 38008 and t2.fld1 =t3.t2nr and period = 1008;
+fld1	companynr	fld3	period
+038008	37	reporters	1008
+038208	37	Selfridge	1008
+select t2.fld1,t2.companynr,fld3,period from t3,t2 where (t2.fld1 = 38208 or t2.fld1 = 38008) and t2.fld1=t3.t2nr and period>=1008 and period<=1009;
+fld1	companynr	fld3	period
+038008	37	reporters	1008
+038208	37	Selfridge	1008
+select t2.fld1,t2.companynr,fld3,period from t3,t2 where (t3.t2nr = 38208 or t3.t2nr = 38008) and t2.fld1=t3.t2nr and period>=1008 and period<=1009;
+fld1	companynr	fld3	period
+038008	37	reporters	1008
+038208	37	Selfridge	1008
+select period from t1 where (((period > 0) or period < 10000 or (period = 1900)) and (period=1900 and period <= 1901) or (period=1903 and (period=1903)) and period>=1902) or ((period=1904 or period=1905) or (period=1906 or period>1907)) or (period=1908 and period = 1909);
+period
+9410
+select period from t1 where ((period > 0 and period < 1) or (((period > 0 and period < 100) and (period > 10)) or (period > 10)) or (period > 0 and (period > 5 or period > 6)));
+period
+9410
+select a.fld1 from t2 as a,t2 b where ((a.fld1 = 250501 and a.fld1=b.fld1) or a.fld1=250502 or a.fld1=250503 or (a.fld1=250505 and a.fld1<=b.fld1 and b.fld1>=a.fld1)) and a.fld1=b.fld1;
+fld1
+250501
+250502
+250503
+250505
+select fld1 from t2 where fld1 in (250502,98005,98006,250503,250605,250606) and fld1 >=250502 and fld1 not in (250605,250606);
+fld1
+250502
+250503
+select fld1 from t2 where fld1 between 250502 and 250504;
+fld1
+250502
+250503
+250504
+select fld3 from t2 where (((fld3 like "_%L%" ) or (fld3 like "%ok%")) and ( fld3 like "L%" or fld3 like "G%")) and fld3 like "L%" ;
+fld3
+label
+labeled
+labeled
+landslide
+laterally
+leaflet
+lewdly
+Lillian
+luckily
+select count(*) from t1;
+count(*)
+1
+select companynr,count(*),sum(fld1) from t2 group by companynr;
+companynr	count(*)	sum(fld1)
+00	82	10355753
+29	95	14473298
+34	70	17788966
+36	215	22786296
+37	588	83602098
+40	37	6618386
+41	52	12816335
+50	11	1595438
+53	4	793210
+58	23	2254293
+65	10	2284055
+68	12	3097288
+select companynr,count(*) from t2 group by companynr order by companynr desc limit 5;
+companynr	count(*)
+68	12
+65	10
+58	23
+53	4
+50	11
+select count(*),min(fld4),max(fld4),sum(fld1),avg(fld1),std(fld1),variance(fld1) from t2 where companynr = 34 and fld4<>"";
+count(*)	min(fld4)	max(fld4)	sum(fld1)	avg(fld1)	std(fld1)	variance(fld1)
+70	absentee	vest	17788966	254128.0857	3272.5940	10709871.3069
+explain extended select count(*),min(fld4),max(fld4),sum(fld1),avg(fld1),std(fld1),variance(fld1) from t2 where companynr = 34 and fld4<>"";
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	100.00	Using where
+Warnings:
+Note	1003	select count(0) AS `count(*)`,min(`test`.`t2`.`fld4`) AS `min(fld4)`,max(`test`.`t2`.`fld4`) AS `max(fld4)`,sum(`test`.`t2`.`fld1`) AS `sum(fld1)`,avg(`test`.`t2`.`fld1`) AS `avg(fld1)`,std(`test`.`t2`.`fld1`) AS `std(fld1)`,variance(`test`.`t2`.`fld1`) AS `variance(fld1)` from `test`.`t2` where ((`test`.`t2`.`companynr` = 34) and (`test`.`t2`.`fld4` <> ''))
+select companynr,count(*),min(fld4),max(fld4),sum(fld1),avg(fld1),std(fld1),variance(fld1) from t2 group by companynr limit 3;
+companynr	count(*)	min(fld4)	max(fld4)	sum(fld1)	avg(fld1)	std(fld1)	variance(fld1)
+00	82	Anthony	windmills	10355753	126289.6707	115550.9757	13352027981.7087
+29	95	abut	wetness	14473298	152350.5053	8368.5480	70032594.9026
+34	70	absentee	vest	17788966	254128.0857	3272.5940	10709871.3069
+select companynr,t2nr,count(price),sum(price),min(price),max(price),avg(price) from t3 where companynr = 37 group by companynr,t2nr limit 10;
+companynr	t2nr	count(price)	sum(price)	min(price)	max(price)	avg(price)
+37	1	1	5987435	5987435	5987435	5987435.0000
+37	2	1	28357832	28357832	28357832	28357832.0000
+37	3	1	39654943	39654943	39654943	39654943.0000
+37	11	1	5987435	5987435	5987435	5987435.0000
+37	12	1	28357832	28357832	28357832	28357832.0000
+37	13	1	39654943	39654943	39654943	39654943.0000
+37	21	1	5987435	5987435	5987435	5987435.0000
+37	22	1	28357832	28357832	28357832	28357832.0000
+37	23	1	39654943	39654943	39654943	39654943.0000
+37	31	1	5987435	5987435	5987435	5987435.0000
+select /*! SQL_SMALL_RESULT */ companynr,t2nr,count(price),sum(price),min(price),max(price),avg(price) from t3 where companynr = 37 group by companynr,t2nr limit 10;
+companynr	t2nr	count(price)	sum(price)	min(price)	max(price)	avg(price)
+37	1	1	5987435	5987435	5987435	5987435.0000
+37	2	1	28357832	28357832	28357832	28357832.0000
+37	3	1	39654943	39654943	39654943	39654943.0000
+37	11	1	5987435	5987435	5987435	5987435.0000
+37	12	1	28357832	28357832	28357832	28357832.0000
+37	13	1	39654943	39654943	39654943	39654943.0000
+37	21	1	5987435	5987435	5987435	5987435.0000
+37	22	1	28357832	28357832	28357832	28357832.0000
+37	23	1	39654943	39654943	39654943	39654943.0000
+37	31	1	5987435	5987435	5987435	5987435.0000
+select companynr,count(price),sum(price),min(price),max(price),avg(price) from t3 group by companynr ;
+companynr	count(price)	sum(price)	min(price)	max(price)	avg(price)
+37	12543	309394878010	5987435	39654943	24666736.6667
+78	8362	414611089292	726498	98439034	49582766.0000
+101	4181	3489454238	834598	834598	834598.0000
+154	4181	4112197254950	983543950	983543950	983543950.0000
+311	4181	979599938	234298	234298	234298.0000
+447	4181	9929180954	2374834	2374834	2374834.0000
+512	4181	3288532102	786542	786542	786542.0000
+select distinct mod(companynr,10) from t4 group by companynr;
+mod(companynr,10)
+0
+9
+4
+6
+7
+1
+3
+8
+5
+select distinct 1 from t4 group by companynr;
+1
+1
+select count(distinct fld1) from t2;
+count(distinct fld1)
+1199
+select companynr,count(distinct fld1) from t2 group by companynr;
+companynr	count(distinct fld1)
+00	82
+29	95
+34	70
+36	215
+37	588
+40	37
+41	52
+50	11
+53	4
+58	23
+65	10
+68	12
+select companynr,count(*) from t2 group by companynr;
+companynr	count(*)
+00	82
+29	95
+34	70
+36	215
+37	588
+40	37
+41	52
+50	11
+53	4
+58	23
+65	10
+68	12
+select companynr,count(distinct concat(fld1,repeat(65,1000))) from t2 group by companynr;
+companynr	count(distinct concat(fld1,repeat(65,1000)))
+00	82
+29	95
+34	70
+36	215
+37	588
+40	37
+41	52
+50	11
+53	4
+58	23
+65	10
+68	12
+select companynr,count(distinct concat(fld1,repeat(65,200))) from t2 group by companynr;
+companynr	count(distinct concat(fld1,repeat(65,200)))
+00	82
+29	95
+34	70
+36	215
+37	588
+40	37
+41	52
+50	11
+53	4
+58	23
+65	10
+68	12
+select companynr,count(distinct floor(fld1/100)) from t2 group by companynr;
+companynr	count(distinct floor(fld1/100))
+00	47
+29	35
+34	14
+36	69
+37	108
+40	16
+41	11
+50	9
+53	1
+58	1
+65	1
+68	1
+select companynr,count(distinct concat(repeat(65,1000),floor(fld1/100))) from t2 group by companynr;
+companynr	count(distinct concat(repeat(65,1000),floor(fld1/100)))
+00	47
+29	35
+34	14
+36	69
+37	108
+40	16
+41	11
+50	9
+53	1
+58	1
+65	1
+68	1
+select sum(fld1),fld3 from t2 where fld3="Romans" group by fld1 limit 10;
+sum(fld1)	fld3
+11402	Romans
+select name,count(*) from t3 where name='cloakroom' group by name;
+name	count(*)
+cloakroom	4181
+select name,count(*) from t3 where name='cloakroom' and price>10 group by name;
+name	count(*)
+cloakroom	4181
+select count(*) from t3 where name='cloakroom' and price2=823742;
+count(*)
+4181
+select name,count(*) from t3 where name='cloakroom' and price2=823742 group by name;
+name	count(*)
+cloakroom	4181
+select name,count(*) from t3 where name >= "extramarital" and price <= 39654943 group by name;
+name	count(*)
+extramarital	4181
+gazer	4181
+gems	4181
+Iranizes	4181
+spates	4181
+tucked	4181
+violinist	4181
+select t2.fld3,count(*) from t2,t3 where t2.fld1=158402 and t3.name=t2.fld3 group by t3.name;
+fld3	count(*)
+spates	4181
+select companynr|0,companyname from t4 group by 1;
+companynr|0	companyname
+0	Unknown
+29	company 1
+34	company 2
+36	company 3
+37	company 4
+40	company 5
+41	company 6
+50	company 11
+53	company 7
+58	company 8
+65	company 9
+68	company 10
+select t2.companynr,companyname,count(*) from t2,t4 where t2.companynr=t4.companynr group by t2.companynr order by companyname;
+companynr	companyname	count(*)
+29	company 1	95
+68	company 10	12
+50	company 11	11
+34	company 2	70
+36	company 3	215
+37	company 4	588
+40	company 5	37
+41	company 6	52
+53	company 7	4
+58	company 8	23
+65	company 9	10
+00	Unknown	82
+select t2.fld1,count(*) from t2,t3 where t2.fld1=158402 and t3.name=t2.fld3 group by t3.name;
+fld1	count(*)
+158402	4181
+select sum(Period)/count(*) from t1;
+sum(Period)/count(*)
+9410.0000
+select companynr,count(price) as "count",sum(price) as "sum" ,abs(sum(price)/count(price)-avg(price)) as "diff",(0+count(price))*companynr as func from t3 group by companynr;
+companynr	count	sum	diff	func
+37	12543	309394878010	0.0000	464091
+78	8362	414611089292	0.0000	652236
+101	4181	3489454238	0.0000	422281
+154	4181	4112197254950	0.0000	643874
+311	4181	979599938	0.0000	1300291
+447	4181	9929180954	0.0000	1868907
+512	4181	3288532102	0.0000	2140672
+select companynr,sum(price)/count(price) as avg from t3 group by companynr having avg > 70000000 order by avg;
+companynr	avg
+154	983543950.0000
+select companynr,count(*) from t2 group by companynr order by 2 desc;
+companynr	count(*)
+37	588
+36	215
+29	95
+00	82
+34	70
+41	52
+40	37
+58	23
+68	12
+50	11
+65	10
+53	4
+select companynr,count(*) from t2 where companynr > 40 group by companynr order by 2 desc;
+companynr	count(*)
+41	52
+58	23
+68	12
+50	11
+65	10
+53	4
+select t2.fld4,t2.fld1,count(price),sum(price),min(price),max(price),avg(price) from t3,t2 where t3.companynr = 37 and t2.fld1 = t3.t2nr group by fld1,t2.fld4;
+fld4	fld1	count(price)	sum(price)	min(price)	max(price)	avg(price)
+teethe	000001	1	5987435	5987435	5987435	5987435.0000
+dreaded	011401	1	5987435	5987435	5987435	5987435.0000
+scholastics	011402	1	28357832	28357832	28357832	28357832.0000
+audiology	011403	1	39654943	39654943	39654943	39654943.0000
+wallet	011501	1	5987435	5987435	5987435	5987435.0000
+parters	011701	1	5987435	5987435	5987435	5987435.0000
+eschew	011702	1	28357832	28357832	28357832	28357832.0000
+quitter	011703	1	39654943	39654943	39654943	39654943.0000
+neat	012001	1	5987435	5987435	5987435	5987435.0000
+Steinberg	012003	1	39654943	39654943	39654943	39654943.0000
+balled	012301	1	5987435	5987435	5987435	5987435.0000
+persist	012302	1	28357832	28357832	28357832	28357832.0000
+attainments	012303	1	39654943	39654943	39654943	39654943.0000
+capably	012501	1	5987435	5987435	5987435	5987435.0000
+impulsive	012602	1	28357832	28357832	28357832	28357832.0000
+starlet	012603	1	39654943	39654943	39654943	39654943.0000
+featherweight	012701	1	5987435	5987435	5987435	5987435.0000
+pessimist	012702	1	28357832	28357832	28357832	28357832.0000
+daughter	012703	1	39654943	39654943	39654943	39654943.0000
+lawgiver	013601	1	5987435	5987435	5987435	5987435.0000
+stated	013602	1	28357832	28357832	28357832	28357832.0000
+readable	013603	1	39654943	39654943	39654943	39654943.0000
+testicle	013801	1	5987435	5987435	5987435	5987435.0000
+Parsifal	013802	1	28357832	28357832	28357832	28357832.0000
+leavings	013803	1	39654943	39654943	39654943	39654943.0000
+squeaking	013901	1	5987435	5987435	5987435	5987435.0000
+contrasted	016001	1	5987435	5987435	5987435	5987435.0000
+leftover	016201	1	5987435	5987435	5987435	5987435.0000
+whiteners	016202	1	28357832	28357832	28357832	28357832.0000
+erases	016301	1	5987435	5987435	5987435	5987435.0000
+Punjab	016302	1	28357832	28357832	28357832	28357832.0000
+Merritt	016303	1	39654943	39654943	39654943	39654943.0000
+sweetish	018001	1	5987435	5987435	5987435	5987435.0000
+dogging	018002	1	28357832	28357832	28357832	28357832.0000
+scornfully	018003	1	39654943	39654943	39654943	39654943.0000
+fetters	018012	1	28357832	28357832	28357832	28357832.0000
+bivalves	018013	1	39654943	39654943	39654943	39654943.0000
+skulking	018021	1	5987435	5987435	5987435	5987435.0000
+flint	018022	1	28357832	28357832	28357832	28357832.0000
+flopping	018023	1	39654943	39654943	39654943	39654943.0000
+Judas	018032	1	28357832	28357832	28357832	28357832.0000
+vacuuming	018033	1	39654943	39654943	39654943	39654943.0000
+medical	018041	1	5987435	5987435	5987435	5987435.0000
+bloodbath	018042	1	28357832	28357832	28357832	28357832.0000
+subschema	018043	1	39654943	39654943	39654943	39654943.0000
+interdependent	018051	1	5987435	5987435	5987435	5987435.0000
+Graves	018052	1	28357832	28357832	28357832	28357832.0000
+neonatal	018053	1	39654943	39654943	39654943	39654943.0000
+sorters	018061	1	5987435	5987435	5987435	5987435.0000
+epistle	018062	1	28357832	28357832	28357832	28357832.0000
+Conley	018101	1	5987435	5987435	5987435	5987435.0000
+lectured	018102	1	28357832	28357832	28357832	28357832.0000
+Abraham	018103	1	39654943	39654943	39654943	39654943.0000
+cage	018201	1	5987435	5987435	5987435	5987435.0000
+hushes	018202	1	28357832	28357832	28357832	28357832.0000
+Simla	018402	1	28357832	28357832	28357832	28357832.0000
+reporters	018403	1	39654943	39654943	39654943	39654943.0000
+coexist	018601	1	5987435	5987435	5987435	5987435.0000
+Beebe	018602	1	28357832	28357832	28357832	28357832.0000
+Taoism	018603	1	39654943	39654943	39654943	39654943.0000
+Connally	018801	1	5987435	5987435	5987435	5987435.0000
+fetched	018802	1	28357832	28357832	28357832	28357832.0000
+checkpoints	018803	1	39654943	39654943	39654943	39654943.0000
+gritty	018811	1	5987435	5987435	5987435	5987435.0000
+firearm	018812	1	28357832	28357832	28357832	28357832.0000
+minima	019101	1	5987435	5987435	5987435	5987435.0000
+Selfridge	019102	1	28357832	28357832	28357832	28357832.0000
+disable	019103	1	39654943	39654943	39654943	39654943.0000
+witchcraft	019201	1	5987435	5987435	5987435	5987435.0000
+betroth	030501	1	5987435	5987435	5987435	5987435.0000
+Manhattanize	030502	1	28357832	28357832	28357832	28357832.0000
+imprint	030503	1	39654943	39654943	39654943	39654943.0000
+swelling	031901	1	5987435	5987435	5987435	5987435.0000
+interrelationships	036001	1	5987435	5987435	5987435	5987435.0000
+riser	036002	1	28357832	28357832	28357832	28357832.0000
+bee	038001	1	5987435	5987435	5987435	5987435.0000
+kanji	038002	1	28357832	28357832	28357832	28357832.0000
+dental	038003	1	39654943	39654943	39654943	39654943.0000
+railway	038011	1	5987435	5987435	5987435	5987435.0000
+validate	038012	1	28357832	28357832	28357832	28357832.0000
+normalizes	038013	1	39654943	39654943	39654943	39654943.0000
+Kline	038101	1	5987435	5987435	5987435	5987435.0000
+Anatole	038102	1	28357832	28357832	28357832	28357832.0000
+partridges	038103	1	39654943	39654943	39654943	39654943.0000
+recruited	038201	1	5987435	5987435	5987435	5987435.0000
+dimensions	038202	1	28357832	28357832	28357832	28357832.0000
+Chicana	038203	1	39654943	39654943	39654943	39654943.0000
+select t3.companynr,fld3,sum(price) from t3,t2 where t2.fld1 = t3.t2nr and t3.companynr = 512 group by companynr,fld3;
+companynr	fld3	sum(price)
+512	boat	786542
+512	capably	786542
+512	cupboard	786542
+512	decliner	786542
+512	descendants	786542
+512	dopers	786542
+512	erases	786542
+512	Micronesia	786542
+512	Miles	786542
+512	skies	786542
+select t2.companynr,count(*),min(fld3),max(fld3),sum(price),avg(price) from t2,t3 where t3.companynr >= 30 and t3.companynr <= 58 and t3.t2nr = t2.fld1 and 1+1=2 group by t2.companynr;
+companynr	count(*)	min(fld3)	max(fld3)	sum(price)	avg(price)
+00	1	Omaha	Omaha	5987435	5987435.0000
+36	1	dubbed	dubbed	28357832	28357832.0000
+37	83	Abraham	Wotan	1908978016	22999735.1325
+50	2	scribbled	tapestry	68012775	34006387.5000
+select t3.companynr+0,t3.t2nr,fld3,sum(price) from t3,t2 where t2.fld1 = t3.t2nr and t3.companynr = 37 group by 1,t3.t2nr,fld3,fld3,fld3,fld3,fld3 order by fld1;
+t3.companynr+0	t2nr	fld3	sum(price)
+37	1	Omaha	5987435
+37	11401	breaking	5987435
+37	11402	Romans	28357832
+37	11403	intercepted	39654943
+37	11501	bewilderingly	5987435
+37	11701	astound	5987435
+37	11702	admonishing	28357832
+37	11703	sumac	39654943
+37	12001	flanking	5987435
+37	12003	combed	39654943
+37	12301	Eulerian	5987435
+37	12302	dubbed	28357832
+37	12303	Kane	39654943
+37	12501	annihilates	5987435
+37	12602	Wotan	28357832
+37	12603	snatching	39654943
+37	12701	grazing	5987435
+37	12702	Baird	28357832
+37	12703	celery	39654943
+37	13601	handgun	5987435
+37	13602	foldout	28357832
+37	13603	mystic	39654943
+37	13801	intelligibility	5987435
+37	13802	Augustine	28357832
+37	13803	teethe	39654943
+37	13901	scholastics	5987435
+37	16001	audiology	5987435
+37	16201	wallet	5987435
+37	16202	parters	28357832
+37	16301	eschew	5987435
+37	16302	quitter	28357832
+37	16303	neat	39654943
+37	18001	jarring	5987435
+37	18002	tinily	28357832
+37	18003	balled	39654943
+37	18012	impulsive	28357832
+37	18013	starlet	39654943
+37	18021	lawgiver	5987435
+37	18022	stated	28357832
+37	18023	readable	39654943
+37	18032	testicle	28357832
+37	18033	Parsifal	39654943
+37	18041	Punjab	5987435
+37	18042	Merritt	28357832
+37	18043	Quixotism	39654943
+37	18051	sureties	5987435
+37	18052	puddings	28357832
+37	18053	tapestry	39654943
+37	18061	trimmings	5987435
+37	18062	humility	28357832
+37	18101	tragedies	5987435
+37	18102	skulking	28357832
+37	18103	flint	39654943
+37	18201	relaxing	5987435
+37	18202	offload	28357832
+37	18402	suites	28357832
+37	18403	lists	39654943
+37	18601	vacuuming	5987435
+37	18602	dentally	28357832
+37	18603	humanness	39654943
+37	18801	inch	5987435
+37	18802	Weissmuller	28357832
+37	18803	irresponsibly	39654943
+37	18811	repetitions	5987435
+37	18812	Antares	28357832
+37	19101	ventilate	5987435
+37	19102	pityingly	28357832
+37	19103	interdependent	39654943
+37	19201	Graves	5987435
+37	30501	neonatal	5987435
+37	30502	scribbled	28357832
+37	30503	chafe	39654943
+37	31901	realtor	5987435
+37	36001	elite	5987435
+37	36002	funereal	28357832
+37	38001	Conley	5987435
+37	38002	lectured	28357832
+37	38003	Abraham	39654943
+37	38011	groupings	5987435
+37	38012	dissociate	28357832
+37	38013	coexist	39654943
+37	38101	rusting	5987435
+37	38102	galling	28357832
+37	38103	obliterates	39654943
+37	38201	resumes	5987435
+37	38202	analyzable	28357832
+37	38203	terminator	39654943
+select sum(price) from t3,t2 where t2.fld1 = t3.t2nr and t3.companynr = 512 and t3.t2nr = 38008 and t2.fld1 = 38008 or t2.fld1= t3.t2nr and t3.t2nr = 38008 and t2.fld1 = 38008;
+sum(price)
+234298
+select t2.fld1,sum(price) from t3,t2 where t2.fld1 = t3.t2nr and t3.companynr = 512 and t3.t2nr = 38008 and t2.fld1 = 38008 or t2.fld1 = t3.t2nr and t3.t2nr = 38008 and t2.fld1 = 38008 or t3.t2nr = t2.fld1 and t2.fld1 = 38008 group by t2.fld1;
+fld1	sum(price)
+038008	234298
+explain select fld3 from t2 where 1>2 or 2>3;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
+explain select fld3 from t2 where fld1=fld1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	
+select companynr,fld1 from t2 HAVING fld1=250501 or fld1=250502;
+companynr	fld1
+34	250501
+34	250502
+select companynr,fld1 from t2 WHERE fld1>=250501 HAVING fld1<=250502;
+companynr	fld1
+34	250501
+34	250502
+select companynr,count(*) as count,sum(fld1) as sum from t2 group by companynr having count > 40 and sum/count >= 120000;
+companynr	count	sum
+00	82	10355753
+29	95	14473298
+34	70	17788966
+37	588	83602098
+41	52	12816335
+select companynr from t2 group by companynr having count(*) > 40 and sum(fld1)/count(*) >= 120000 ;
+companynr
+00
+29
+34
+37
+41
+select t2.companynr,companyname,count(*) from t2,t4 where t2.companynr=t4.companynr group by companyname having t2.companynr >= 40;
+companynr	companyname	count(*)
+68	company 10	12
+50	company 11	11
+40	company 5	37
+41	company 6	52
+53	company 7	4
+58	company 8	23
+65	company 9	10
+select count(*) from t2;
+count(*)
+1199
+select count(*) from t2 where fld1 < 098024;
+count(*)
+387
+select min(fld1) from t2 where fld1>= 098024;
+min(fld1)
+98024
+select max(fld1) from t2 where fld1>= 098024;
+max(fld1)
+1232609
+select count(*) from t3 where price2=76234234;
+count(*)
+4181
+select count(*) from t3 where companynr=512 and price2=76234234;
+count(*)
+4181
+explain select min(fld1),max(fld1),count(*) from t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+select min(fld1),max(fld1),count(*) from t2;
+min(fld1)	max(fld1)	count(*)
+0	1232609	1199
+select min(t2nr),max(t2nr) from t3 where t2nr=2115 and price2=823742;
+min(t2nr)	max(t2nr)
+2115	2115
+select count(*),min(t2nr),max(t2nr) from t3 where name='spates' and companynr=78;
+count(*)	min(t2nr)	max(t2nr)
+4181	4	41804
+select t2nr,count(*) from t3 where name='gems' group by t2nr limit 20;
+t2nr	count(*)
+9	1
+19	1
+29	1
+39	1
+49	1
+59	1
+69	1
+79	1
+89	1
+99	1
+109	1
+119	1
+129	1
+139	1
+149	1
+159	1
+169	1
+179	1
+189	1
+199	1
+select max(t2nr) from t3 where price=983543950;
+max(t2nr)
+41807
+select t1.period from t3 = t1 limit 1;
+period
+1001
+select t1.period from t1 as t1 limit 1;
+period
+9410
+select t1.period as "Nuvarande period" from t1 as t1 limit 1;
+Nuvarande period
+9410
+select period as ok_period from t1 limit 1;
+ok_period
+9410
+select period as ok_period from t1 group by ok_period limit 1;
+ok_period
+9410
+select 1+1 as summa from t1 group by summa limit 1;
+summa
+2
+select period as "Nuvarande period" from t1 group by "Nuvarande period" limit 1;
+Nuvarande period
+9410
+show tables;
+Tables_in_test
+t1
+t2
+t3
+t4
+show tables from test like "s%";
+Tables_in_test (s%)
+show tables from test like "t?";
+Tables_in_test (t?)
+show full columns from t2;
+Field	Type	Collation	Null	Key	Default	Extra	Privileges	Comment
+auto	int(11)	NULL	NO	PRI	NULL	auto_increment	#	
+fld1	int(6) unsigned zerofill	NULL	NO	UNI	000000		#	
+companynr	tinyint(2) unsigned zerofill	NULL	NO		00		#	
+fld3	char(30)	latin1_swedish_ci	NO	MUL			#	
+fld4	char(35)	latin1_swedish_ci	NO				#	
+fld5	char(35)	latin1_swedish_ci	NO				#	
+fld6	char(4)	latin1_swedish_ci	NO				#	
+show full columns from t2 from test like 'f%';
+Field	Type	Collation	Null	Key	Default	Extra	Privileges	Comment
+fld1	int(6) unsigned zerofill	NULL	NO	UNI	000000		#	
+fld3	char(30)	latin1_swedish_ci	NO	MUL			#	
+fld4	char(35)	latin1_swedish_ci	NO				#	
+fld5	char(35)	latin1_swedish_ci	NO				#	
+fld6	char(4)	latin1_swedish_ci	NO				#	
+show full columns from t2 from test like 's%';
+Field	Type	Collation	Null	Key	Default	Extra	Privileges	Comment
+show keys from t2;
+Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment
+t2	0	PRIMARY	1	auto	A	1199	NULL	NULL		BTREE	
+t2	0	fld1	1	fld1	A	1199	NULL	NULL		BTREE	
+t2	1	fld3	1	fld3	A	NULL	NULL	NULL		BTREE	
+drop table t4, t3, t2, t1;
+DO 1;
+DO benchmark(100,1+1),1,1;
+do default;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
+do foobar;
+ERROR 42S22: Unknown column 'foobar' in 'field list'
+CREATE TABLE t1 (
+id mediumint(8) unsigned NOT NULL auto_increment,
+pseudo varchar(35) NOT NULL default '',
+PRIMARY KEY  (id),
+UNIQUE KEY pseudo (pseudo)
+);
+INSERT INTO t1 (pseudo) VALUES ('test');
+INSERT INTO t1 (pseudo) VALUES ('test1');
+SELECT 1 as rnd1 from t1 where rand() > 2;
+rnd1
+DROP TABLE t1;
+CREATE TABLE t1 (gvid int(10) unsigned default NULL,  hmid int(10) unsigned default NULL,  volid int(10) unsigned default NULL,  mmid int(10) unsigned default NULL,  hdid int(10) unsigned default NULL,  fsid int(10) unsigned default NULL,  ctid int(10) unsigned default NULL,  dtid int(10) unsigned default NULL,  cost int(10) unsigned default NULL,  performance int(10) unsigned default NULL,  serialnumber bigint(20) unsigned default NULL,  monitored tinyint(3) unsigned default '1',  removed tinyint(3) unsigned default '0',  target tinyint(3) unsigned default '0',  dt_modified timestamp NOT NULL,  name varchar(255) binary default NULL,  description varchar(255) default NULL,  UNIQUE KEY hmid (hmid,volid)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (200001,2,1,1,100,1,1,1,0,0,0,1,0,1,20020425060057,'\\\\ARKIVIO-TESTPDC\\E$',''),(200002,2,2,1,101,1,1,1,0,0,0,1,0,1,20020425060057,'\\\\ARKIVIO-TESTPDC\\C$',''),(200003,1,3,2,NULL,NULL,NULL,NULL,NULL,NULL,NULL,1,0,1,20020425060427,'c:',NULL);
+CREATE TABLE t2 (  hmid int(10) unsigned default NULL,  volid int(10) unsigned default NULL,  sampletid smallint(5) unsigned default NULL,  sampletime datetime default NULL,  samplevalue bigint(20) unsigned default NULL,  KEY idx1 (hmid,volid,sampletid,sampletime)) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (1,3,10,'2002-06-01 08:00:00',35),(1,3,1010,'2002-06-01 12:00:01',35);
+SELECT a.gvid, (SUM(CASE b.sampletid WHEN 140 THEN b.samplevalue ELSE 0 END)) as the_success,(SUM(CASE b.sampletid WHEN 141 THEN b.samplevalue ELSE 0 END)) as the_fail,(SUM(CASE b.sampletid WHEN 142 THEN b.samplevalue ELSE 0 END)) as the_size,(SUM(CASE b.sampletid WHEN 143 THEN b.samplevalue ELSE 0 END)) as the_time FROM t1 a, t2 b WHERE a.hmid = b.hmid AND a.volid = b.volid AND b.sampletime >= 'wrong-date-value' AND b.sampletime < 'wrong-date-value' AND b.sampletid IN (140, 141, 142, 143) GROUP BY a.gvid;
+gvid	the_success	the_fail	the_size	the_time
+Warnings:
+Warning	1292	Incorrect datetime value: 'wrong-date-value' for column 'sampletime' at row 1
+Warning	1292	Incorrect datetime value: 'wrong-date-value' for column 'sampletime' at row 1
+SELECT a.gvid, (SUM(CASE b.sampletid WHEN 140 THEN b.samplevalue ELSE 0 END)) as the_success,(SUM(CASE b.sampletid WHEN 141 THEN b.samplevalue ELSE 0 END)) as the_fail,(SUM(CASE b.sampletid WHEN 142 THEN b.samplevalue ELSE 0 END)) as the_size,(SUM(CASE b.sampletid WHEN 143 THEN b.samplevalue ELSE 0 END)) as the_time FROM t1 a, t2 b WHERE a.hmid = b.hmid AND a.volid = b.volid AND b.sampletime >= NULL AND b.sampletime < NULL AND b.sampletid IN (140, 141, 142, 143) GROUP BY a.gvid;
+gvid	the_success	the_fail	the_size	the_time
+DROP TABLE t1,t2;
+create table  t1 (  A_Id bigint(20) NOT NULL default '0',  A_UpdateBy char(10) NOT NULL default '',  A_UpdateDate bigint(20) NOT NULL default '0',  A_UpdateSerial int(11) NOT NULL default '0',  other_types bigint(20) NOT NULL default '0',  wss_type bigint(20) NOT NULL default '0');
+INSERT INTO t1 VALUES (102935998719055004,'brade',1029359987,2,102935229116544068,102935229216544093);
+select wss_type from t1 where wss_type ='102935229216544106';
+wss_type
+select wss_type from t1 where wss_type ='102935229216544105';
+wss_type
+select wss_type from t1 where wss_type ='102935229216544104';
+wss_type
+select wss_type from t1 where wss_type ='102935229216544093';
+wss_type
+102935229216544093
+select wss_type from t1 where wss_type =102935229216544093;
+wss_type
+102935229216544093
+drop table t1;
+select 1+2,"aaaa",3.13*2.0 into @a,@b,@c;
+select @a;
+@a
+3
+select @b;
+@b
+aaaa
+select @c;
+@c
+6.260
+create table t1 (a int not null auto_increment primary key);
+insert into t1 values ();
+insert into t1 values ();
+insert into t1 values ();
+select * from (t1 as t2 left join t1 as t3 using (a)), t1;
+a	a
+1	1
+2	1
+3	1
+1	2
+2	2
+3	2
+1	3
+2	3
+3	3
+select * from t1, (t1 as t2 left join t1 as t3 using (a));
+a	a
+1	1
+2	1
+3	1
+1	2
+2	2
+3	2
+1	3
+2	3
+3	3
+select * from (t1 as t2 left join t1 as t3 using (a)) straight_join t1;
+a	a
+1	1
+2	1
+3	1
+1	2
+2	2
+3	2
+1	3
+2	3
+3	3
+select * from t1 straight_join (t1 as t2 left join t1 as t3 using (a));
+a	a
+1	1
+2	1
+3	1
+1	2
+2	2
+3	2
+1	3
+2	3
+3	3
+select * from (t1 as t2 left join t1 as t3 using (a)) inner join t1 on t1.a>1;
+a	a
+1	2
+2	2
+3	2
+1	3
+2	3
+3	3
+select * from t1 inner join (t1 as t2 left join t1 as t3 using (a)) on t1.a>1;
+a	a
+2	1
+3	1
+2	2
+3	2
+2	3
+3	3
+select * from (t1 as t2 left join t1 as t3 using (a)) inner join t1 using ( a );
+a
+1
+2
+3
+select * from t1 inner join (t1 as t2 left join t1 as t3 using (a)) using ( a );
+a
+1
+2
+3
+select * from (t1 as t2 left join t1 as t3 using (a)) left outer join t1 on t1.a>1;
+a	a
+1	2
+1	3
+2	2
+2	3
+3	2
+3	3
+select * from t1 left outer join (t1 as t2 left join t1 as t3 using (a)) on t1.a>1;
+a	a
+1	NULL
+2	1
+2	2
+2	3
+3	1
+3	2
+3	3
+select * from (t1 as t2 left join t1 as t3 using (a)) left join t1 using ( a );
+a
+1
+2
+3
+select * from t1 left join (t1 as t2 left join t1 as t3 using (a)) using ( a );
+a
+1
+2
+3
+select * from (t1 as t2 left join t1 as t3 using (a)) natural left join t1;
+a
+1
+2
+3
+select * from t1 natural left join (t1 as t2 left join t1 as t3 using (a));
+a
+1
+2
+3
+select * from (t1 as t2 left join t1 as t3 using (a)) right join t1 on t1.a>1;
+a	a
+NULL	1
+1	2
+2	2
+3	2
+1	3
+2	3
+3	3
+select * from t1 right join (t1 as t2 left join t1 as t3 using (a)) on t1.a>1;
+a	a
+2	1
+3	1
+2	2
+3	2
+2	3
+3	3
+select * from (t1 as t2 left join t1 as t3 using (a)) right outer join t1 using ( a );
+a
+1
+2
+3
+select * from t1 right outer join (t1 as t2 left join t1 as t3 using (a)) using ( a );
+a
+1
+2
+3
+select * from (t1 as t2 left join t1 as t3 using (a)) natural right join t1;
+a
+1
+2
+3
+select * from t1 natural right join (t1 as t2 left join t1 as t3 using (a));
+a
+1
+2
+3
+select * from t1 natural join (t1 as t2 left join t1 as t3 using (a));
+a
+1
+2
+3
+select * from (t1 as t2 left join t1 as t3 using (a)) natural join t1;
+a
+1
+2
+3
+drop table t1;
+CREATE TABLE t1 (  aa char(2),  id int(11) NOT NULL auto_increment,  t2_id int(11) NOT NULL default '0',  PRIMARY KEY  (id),  KEY replace_id (t2_id)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES ("1",8264,2506),("2",8299,2517),("3",8301,2518),("4",8302,2519),("5",8303,2520),("6",8304,2521),("7",8305,2522);
+CREATE TABLE t2 ( id int(11) NOT NULL auto_increment,  PRIMARY KEY  (id)) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (2517), (2518), (2519), (2520), (2521), (2522);
+select * from t1, t2 WHERE t1.t2_id = t2.id and t1.t2_id > 0   order by t1.id   LIMIT 0, 5;
+aa	id	t2_id	id
+2	8299	2517	2517
+3	8301	2518	2518
+4	8302	2519	2519
+5	8303	2520	2520
+6	8304	2521	2521
+drop table t1,t2;
+create table t1 (id1 int NOT NULL);
+create table t2 (id2 int NOT NULL);
+create table t3 (id3 int NOT NULL);
+create table t4 (id4 int NOT NULL, id44 int NOT NULL, KEY (id4));
+insert into t1 values (1);
+insert into t1 values (2);
+insert into t2 values (1);
+insert into t4 values (1,1);
+explain select * from t1 left join t2 on id1 = id2 left join t3 on id1 = id3
+left join t4 on id3 = id4 where id2 = 1 or id4 = 1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t3	system	NULL	NULL	NULL	NULL	0	const row not found
+1	SIMPLE	t4	const	id4	NULL	NULL	NULL	1	
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1	Using where
+select * from t1 left join t2 on id1 = id2 left join t3 on id1 = id3
+left join t4 on id3 = id4 where id2 = 1 or id4 = 1;
+id1	id2	id3	id4	id44
+1	1	NULL	NULL	NULL
+drop table t1,t2,t3,t4;
+create table t1(s varchar(10) not null);
+create table t2(s varchar(10) not null primary key);
+create table t3(s varchar(10) not null primary key);
+insert into t1 values ('one\t'), ('two\t');
+insert into t2 values ('one\r'), ('two\t');
+insert into t3 values ('one '), ('two\t');
+select * from t1 where s = 'one';
+s
+select * from t2 where s = 'one';
+s
+select * from t3 where s = 'one';
+s
+one 
+select * from t1,t2 where t1.s = t2.s;
+s	s
+two		two	
+select * from t2,t3 where t2.s = t3.s;
+s	s
+two		two	
+drop table t1, t2, t3;
+create table t1 (a integer,  b integer, index(a), index(b));
+create table t2 (c integer,  d integer, index(c), index(d));
+insert into t1 values (1,2), (2,2), (3,2), (4,2);
+insert into t2 values (1,3), (2,3), (3,4), (4,4);
+explain select * from t1 left join t2 on a=c where d in (4);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	c,d	d	5	const	2	Using where
+1	SIMPLE	t1	ALL	a	NULL	NULL	NULL	4	Using where; Using join buffer
+select * from t1 left join t2 on a=c where d in (4);
+a	b	c	d
+3	2	3	4
+4	2	4	4
+explain select * from t1 left join t2 on a=c where d = 4;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	c,d	d	5	const	2	Using where
+1	SIMPLE	t1	ALL	a	NULL	NULL	NULL	4	Using where; Using join buffer
+select * from t1 left join t2 on a=c where d = 4;
+a	b	c	d
+3	2	3	4
+4	2	4	4
+drop table t1, t2;
+CREATE TABLE t1 (
+i int(11) NOT NULL default '0',
+c char(10) NOT NULL default '',
+PRIMARY KEY  (i),
+UNIQUE KEY c (c)
+) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (1,'a');
+INSERT INTO t1 VALUES (2,'b');
+INSERT INTO t1 VALUES (3,'c');
+EXPLAIN SELECT i FROM t1 WHERE i=1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	Using index
+DROP TABLE t1;
+CREATE TABLE t1 ( a BLOB, INDEX (a(20)) );
+CREATE TABLE t2 ( a BLOB, INDEX (a(20)) );
+INSERT INTO t1 VALUES ('one'),('two'),('three'),('four'),('five');
+INSERT INTO t2 VALUES ('one'),('two'),('three'),('four'),('five');
+EXPLAIN SELECT * FROM t1 LEFT JOIN t2 USE INDEX (a) ON t1.a=t2.a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	
+1	SIMPLE	t2	ref	a	a	23	test.t1.a	2	
+EXPLAIN SELECT * FROM t1 LEFT JOIN t2 FORCE INDEX (a) ON t1.a=t2.a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	
+1	SIMPLE	t2	ref	a	a	23	test.t1.a	2	
+DROP TABLE t1, t2;
+CREATE TABLE t1 ( city char(30) );
+INSERT INTO t1 VALUES ('London');
+INSERT INTO t1 VALUES ('Paris');
+SELECT * FROM t1 WHERE city='London';
+city
+London
+SELECT * FROM t1 WHERE city='london';
+city
+London
+EXPLAIN SELECT * FROM t1 WHERE city='London' AND city='london';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+SELECT * FROM t1 WHERE city='London' AND city='london';
+city
+London
+EXPLAIN SELECT * FROM t1 WHERE city LIKE '%london%' AND city='London';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+SELECT * FROM t1 WHERE city LIKE '%london%' AND city='London';
+city
+London
+DROP TABLE t1;
+create table t1 (a int(11) unsigned, b int(11) unsigned);
+insert into t1 values (1,0), (1,1), (1,2);
+select a-b  from t1 order by 1;
+a-b
+0
+1
+18446744073709551615
+select a-b , (a-b < 0)  from t1 order by 1;
+a-b	(a-b < 0)
+0	0
+1	0
+18446744073709551615	0
+select a-b as d, (a-b >= 0), b from t1 group by b having d >= 0;
+d	(a-b >= 0)	b
+1	1	0
+0	1	1
+18446744073709551615	1	2
+select cast((a - b) as unsigned) from t1 order by 1;
+cast((a - b) as unsigned)
+0
+1
+18446744073709551615
+drop table t1;
+create table t1 (a int(11));
+select all all * from t1;
+a
+select distinct distinct * from t1;
+a
+select all distinct * from t1;
+ERROR HY000: Incorrect usage of ALL and DISTINCT
+select distinct all * from t1;
+ERROR HY000: Incorrect usage of ALL and DISTINCT
+drop table t1;
+CREATE TABLE t1 (
+kunde_intern_id int(10) unsigned NOT NULL default '0',
+kunde_id int(10) unsigned NOT NULL default '0',
+FK_firma_id int(10) unsigned NOT NULL default '0',
+aktuell enum('Ja','Nein') NOT NULL default 'Ja',
+vorname varchar(128) NOT NULL default '',
+nachname varchar(128) NOT NULL default '',
+geloescht enum('Ja','Nein') NOT NULL default 'Nein',
+firma varchar(128) NOT NULL default ''
+);
+INSERT INTO t1 VALUES 
+(3964,3051,1,'Ja','Vorname1','1Nachname','Nein','Print Schau XXXX'),
+(3965,3051111,1,'Ja','Vorname1111','1111Nachname','Nein','Print Schau XXXX');
+SELECT kunde_id ,FK_firma_id ,aktuell, vorname, nachname, geloescht FROM t1
+WHERE
+(
+(
+( '' != '' AND firma LIKE CONCAT('%', '', '%'))
+OR
+(vorname LIKE CONCAT('%', 'Vorname1', '%') AND 
+nachname LIKE CONCAT('%', '1Nachname', '%') AND 
+'Vorname1' != '' AND 'xxxx' != '')
+)
+AND
+(
+aktuell = 'Ja' AND geloescht = 'Nein' AND FK_firma_id = 2
+)
+)
+;
+kunde_id	FK_firma_id	aktuell	vorname	nachname	geloescht
+SELECT kunde_id ,FK_firma_id ,aktuell, vorname, nachname,
+geloescht FROM t1
+WHERE
+(
+(
+aktuell = 'Ja' AND geloescht = 'Nein' AND FK_firma_id = 2
+)
+AND
+(
+( '' != '' AND firma LIKE CONCAT('%', '', '%')  )
+OR
+(  vorname LIKE CONCAT('%', 'Vorname1', '%') AND
+nachname LIKE CONCAT('%', '1Nachname', '%') AND 'Vorname1' != '' AND
+'xxxx' != '')
+)
+)
+;
+kunde_id	FK_firma_id	aktuell	vorname	nachname	geloescht
+SELECT COUNT(*) FROM t1 WHERE 
+( 0 OR (vorname LIKE '%Vorname1%' AND nachname LIKE '%1Nachname%' AND 1)) 
+AND FK_firma_id = 2;
+COUNT(*)
+0
+drop table t1;
+CREATE TABLE t1 (b BIGINT(20) UNSIGNED NOT NULL, PRIMARY KEY (b));
+INSERT INTO t1 VALUES (0x8000000000000000);
+SELECT b FROM t1 WHERE b=0x8000000000000000;
+b
+9223372036854775808
+DROP TABLE t1;
+CREATE TABLE `t1` ( `gid` int(11) default NULL, `uid` int(11) default NULL);
+CREATE TABLE `t2` ( `ident` int(11) default NULL, `level` char(16) default NULL);
+INSERT INTO `t2` VALUES (0,'READ');
+CREATE TABLE `t3` ( `id` int(11) default NULL, `name` char(16) default NULL);
+INSERT INTO `t3` VALUES (1,'fs');
+select * from t3 left join t1 on t3.id = t1.uid, t2 where t2.ident in (0, t1.gid, t3.id, 0);
+id	name	gid	uid	ident	level
+1	fs	NULL	NULL	0	READ
+drop table t1,t2,t3;
+CREATE TABLE t1 (
+acct_id int(11) NOT NULL default '0',
+profile_id smallint(6) default NULL,
+UNIQUE KEY t1$acct_id (acct_id),
+KEY t1$profile_id (profile_id)
+);
+INSERT INTO t1 VALUES (132,17),(133,18);
+CREATE TABLE t2 (
+profile_id smallint(6) default NULL,
+queue_id int(11) default NULL,
+seq int(11) default NULL,
+KEY t2$queue_id (queue_id)
+);
+INSERT INTO t2 VALUES (17,31,4),(17,30,3),(17,36,2),(17,37,1);
+CREATE TABLE t3 (
+id int(11) NOT NULL default '0',
+qtype int(11) default NULL,
+seq int(11) default NULL,
+warn_lvl int(11) default NULL,
+crit_lvl int(11) default NULL,
+rr1 tinyint(4) NOT NULL default '0',
+rr2 int(11) default NULL,
+default_queue tinyint(4) NOT NULL default '0',
+KEY t3$qtype (qtype),
+KEY t3$id (id)
+);
+INSERT INTO t3 VALUES (30,1,29,NULL,NULL,0,NULL,0),(31,1,28,NULL,NULL,0,NULL,0),
+(36,1,34,NULL,NULL,0,NULL,0),(37,1,35,NULL,NULL,0,121,0);
+SELECT COUNT(*) FROM t1 a STRAIGHT_JOIN t2 pq STRAIGHT_JOIN t3 q 
+WHERE 
+(pq.profile_id = a.profile_id) AND (a.acct_id = 132) AND 
+(pq.queue_id = q.id) AND (q.rr1 <> 1);
+COUNT(*)
+4
+drop table t1,t2,t3;
+create table t1 (f1 int);
+insert into t1 values (1),(NULL);
+create table t2 (f2 int, f3 int, f4 int);
+create index idx1 on t2 (f4);
+insert into t2 values (1,2,3),(2,4,6);
+select A.f2 from t1 left join t2 A on A.f2 = f1 where A.f3=(select min(f3)
+from  t2 C where A.f4 = C.f4) or A.f3 IS NULL;
+f2
+1
+NULL
+drop table t1,t2;
+create table t2 (a tinyint unsigned);
+create index t2i on t2(a);
+insert into t2 values (0), (254), (255);
+explain select * from t2 where a > -1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	t2i	t2i	2	NULL	3	Using where; Using index
+select * from t2 where a > -1;
+a
+0
+254
+255
+drop table t2;
+CREATE TABLE t1 (a int, b int, c int);
+INSERT INTO t1
+SELECT 50, 3, 3 FROM DUAL
+WHERE NOT EXISTS
+(SELECT * FROM t1 WHERE a = 50 AND b = 3);
+SELECT * FROM t1;
+a	b	c
+50	3	3
+INSERT INTO t1
+SELECT 50, 3, 3 FROM DUAL
+WHERE NOT EXISTS
+(SELECT * FROM t1 WHERE a = 50 AND b = 3);
+select found_rows();
+found_rows()
+0
+SELECT * FROM t1;
+a	b	c
+50	3	3
+select count(*) from t1;
+count(*)
+1
+select found_rows();
+found_rows()
+1
+select count(*) from t1 limit 2,3;
+count(*)
+select found_rows();
+found_rows()
+0
+select SQL_CALC_FOUND_ROWS count(*) from t1 limit 2,3;
+count(*)
+select found_rows();
+found_rows()
+1
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, b INT);
+(SELECT a, b AS c FROM t1) ORDER BY c+1;
+a	c
+(SELECT a, b AS c FROM t1) ORDER BY b+1;
+a	c
+SELECT a, b AS c FROM t1 ORDER BY c+1;
+a	c
+SELECT a, b AS c FROM t1 ORDER BY b+1;
+a	c
+drop table t1;
+create table t1(f1 int, f2 int);
+create table t2(f3 int);
+select f1 from t1,t2 where f1=f2 and (f1,f2) = ((1,1));
+f1
+select f1 from t1,t2 where f1=f2 and (f1,NULL) = ((1,1));
+f1
+select f1 from t1,t2 where f1=f2 and (f1,f2) = ((1,NULL));
+f1
+insert into t1 values(1,1),(2,null);
+insert into t2 values(2);
+select * from t1,t2 where f1=f3 and (f1,f2) = (2,null);
+f1	f2	f3
+select * from t1,t2 where f1=f3 and (f1,f2) <=> (2,null);
+f1	f2	f3
+2	NULL	2
+drop table t1,t2;
+create table t1 (f1 int not null auto_increment primary key, f2 varchar(10));
+create table t11 like t1;
+insert into t1 values(1,""),(2,"");
+show table status like 't1%';
+Name	Engine	Version	Row_format	Rows	Avg_row_length	Data_length	Max_data_length	Index_length	Data_free	Auto_increment	Create_time	Update_time	Check_time	Collation	Checksum	Create_options	Comment
+t1	MyISAM	10	Dynamic	2	20	X	X	X	X	X	X	X	X	latin1_swedish_ci	NULL		
+t11	MyISAM	10	Dynamic	0	0	X	X	X	X	X	X	X	X	latin1_swedish_ci	NULL		
+select 123 as a from t1 where f1 is null;
+a
+drop table t1,t11;
+CREATE TABLE t1 ( a INT NOT NULL, b INT NOT NULL, UNIQUE idx (a,b) );
+INSERT INTO t1 VALUES (1,1),(1,2),(1,3),(1,4);
+CREATE TABLE t2 ( a INT NOT NULL, b INT NOT NULL, e INT );
+INSERT INTO t2 VALUES ( 1,10,1), (1,10,2), (1,11,1), (1,11,2), (1,2,1), (1,2,2),(1,2,3);
+SELECT t2.a, t2.b, IF(t1.b IS NULL,'',e) AS c, COUNT(*) AS d FROM t2 LEFT JOIN
+t1 ON t2.a = t1.a AND t2.b = t1.b GROUP BY a, b, c;
+a	b	c	d
+1	2	1	1
+1	2	2	1
+1	2	3	1
+1	10		2
+1	11		2
+SELECT t2.a, t2.b, IF(t1.b IS NULL,'',e) AS c, COUNT(*) AS d FROM t2 LEFT JOIN
+t1 ON t2.a = t1.a AND t2.b = t1.b GROUP BY t1.a, t1.b, c;
+a	b	c	d
+1	10		4
+1	2	1	1
+1	2	2	1
+1	2	3	1
+SELECT t2.a, t2.b, IF(t1.b IS NULL,'',e) AS c, COUNT(*) AS d FROM t2 LEFT JOIN
+t1 ON t2.a = t1.a AND t2.b = t1.b GROUP BY t2.a, t2.b, c;
+a	b	c	d
+1	2	1	1
+1	2	2	1
+1	2	3	1
+1	10		2
+1	11		2
+SELECT t2.a, t2.b, IF(t1.b IS NULL,'',e) AS c, COUNT(*) AS d FROM t2,t1
+WHERE t2.a = t1.a AND t2.b = t1.b GROUP BY a, b, c;
+a	b	c	d
+1	2	1	1
+1	2	2	1
+1	2	3	1
+DROP TABLE IF EXISTS t1, t2;
+create table t1 (f1 int primary key, f2 int);
+create table t2 (f3 int, f4 int, primary key(f3,f4));
+insert into t1 values (1,1);
+insert into t2 values (1,1),(1,2);
+select distinct count(f2) >0 from t1 left join t2 on f1=f3 group by f1;
+count(f2) >0
+1
+drop table t1,t2;
+create table t1 (f1 int,f2 int);
+insert into t1 values(1,1);
+create table t2 (f3 int, f4 int, primary key(f3,f4));
+insert into t2 values(1,1);
+select * from t1 where f1 in (select f3 from t2 where (f3,f4)= (select f3,f4 from t2));
+f1	f2
+1	1
+drop table t1,t2;
+CREATE TABLE t1(a int, b int, c int, KEY b(b), KEY c(c));
+insert into t1 values (1,0,0),(2,0,0);
+CREATE TABLE t2 (a int, b varchar(2), c varchar(2), PRIMARY KEY(a));
+insert into t2 values (1,'',''), (2,'','');
+CREATE TABLE t3 (a int, b int, PRIMARY KEY (a,b), KEY a (a), KEY b (b));
+insert into t3 values (1,1),(1,2);
+explain select straight_join DISTINCT t2.a,t2.b, t1.c from t1, t3, t2 
+where (t1.c=t2.a or (t1.c=t3.a and t2.a=t3.b)) and t1.b=556476786 and 
+t2.b like '%%' order by t2.b limit 0,1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	b,c	b	5	const	1	Using where; Using temporary; Using filesort
+1	SIMPLE	t3	index	PRIMARY,a,b	PRIMARY	8	NULL	2	Using index; Using join buffer
+1	SIMPLE	t2	ALL	PRIMARY	NULL	NULL	NULL	2	Range checked for each record (index map: 0x1)
+DROP TABLE t1,t2,t3;
+CREATE TABLE t1 (a int, INDEX idx(a));
+INSERT INTO t1 VALUES (2), (3), (1);
+EXPLAIN SELECT * FROM t1 IGNORE INDEX (idx);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+EXPLAIN SELECT * FROM t1 IGNORE INDEX (a);
+ERROR 42000: Key 'a' doesn't exist in table 't1'
+EXPLAIN SELECT * FROM t1 FORCE INDEX (a);
+ERROR 42000: Key 'a' doesn't exist in table 't1'
+DROP TABLE t1;
+CREATE TABLE t1 (a int, b int);
+INSERT INTO t1 VALUES (1,1), (2,1), (4,10);
+CREATE TABLE t2 (a int PRIMARY KEY, b int, KEY b (b));
+INSERT INTO t2 VALUES (1,NULL), (2,10);
+ALTER TABLE t1 ENABLE KEYS;
+EXPLAIN SELECT STRAIGHT_JOIN SQL_NO_CACHE COUNT(*) FROM t2, t1 WHERE t1.b = t2.b OR t2.b IS NULL;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	b	b	5	NULL	2	Using index
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	Using where; Using join buffer
+SELECT STRAIGHT_JOIN SQL_NO_CACHE * FROM t2, t1 WHERE t1.b = t2.b OR t2.b IS NULL;
+a	b	a	b
+1	NULL	1	1
+1	NULL	2	1
+1	NULL	4	10
+2	10	4	10
+EXPLAIN SELECT STRAIGHT_JOIN SQL_NO_CACHE COUNT(*) FROM t2, t1 WHERE t1.b = t2.b OR t2.b IS NULL;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	b	b	5	NULL	2	Using index
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	Using where; Using join buffer
+SELECT STRAIGHT_JOIN SQL_NO_CACHE * FROM t2, t1 WHERE t1.b = t2.b OR t2.b IS NULL;
+a	b	a	b
+1	NULL	1	1
+1	NULL	2	1
+1	NULL	4	10
+2	10	4	10
+DROP TABLE IF EXISTS t1,t2;
+CREATE TABLE t1 (key1 float default NULL, UNIQUE KEY key1 (key1));
+CREATE TABLE t2 (key2 float default NULL, UNIQUE KEY key2 (key2));
+INSERT INTO t1 VALUES (0.3762),(0.3845),(0.6158),(0.7941);
+INSERT INTO t2 VALUES (1.3762),(1.3845),(1.6158),(1.7941);
+explain select max(key1) from t1 where key1 <= 0.6158;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+explain select max(key2) from t2 where key2 <= 1.6158;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+explain select min(key1) from t1 where key1 >= 0.3762;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+explain select min(key2) from t2 where key2 >= 1.3762;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+explain select max(key1), min(key2) from t1, t2
+where key1 <= 0.6158 and key2 >= 1.3762;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+explain select max(key1) from t1 where key1 <= 0.6158 and rand() + 0.5 >= 0.5;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+explain select min(key1) from t1 where key1 >= 0.3762 and rand() + 0.5 >= 0.5;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+select max(key1) from t1 where key1 <= 0.6158;
+max(key1)
+0.615800023078918
+select max(key2) from t2 where key2 <= 1.6158;
+max(key2)
+1.61580002307892
+select min(key1) from t1 where key1 >= 0.3762;
+min(key1)
+0.376199990510941
+select min(key2) from t2 where key2 >= 1.3762;
+min(key2)
+1.37619996070862
+select max(key1), min(key2) from t1, t2
+where key1 <= 0.6158 and key2 >= 1.3762;
+max(key1)	min(key2)
+0.615800023078918	1.37619996070862
+select max(key1) from t1 where key1 <= 0.6158 and rand() + 0.5 >= 0.5;
+max(key1)
+0.615800023078918
+select min(key1) from t1 where key1 >= 0.3762 and rand() + 0.5 >= 0.5;
+min(key1)
+0.376199990510941
+DROP TABLE t1,t2;
+CREATE TABLE t1 (i BIGINT UNSIGNED NOT NULL);
+INSERT INTO t1 VALUES (10);
+SELECT i='1e+01',i=1e+01, i in (1e+01,1e+01), i in ('1e+01','1e+01') FROM t1;
+i='1e+01'	i=1e+01	i in (1e+01,1e+01)	i in ('1e+01','1e+01')
+1	1	1	1
+DROP TABLE t1;
+create table t1(a bigint unsigned, b bigint);
+insert into t1 values (0xfffffffffffffffff, 0xfffffffffffffffff), 
+(0x10000000000000000, 0x10000000000000000), 
+(0x8fffffffffffffff, 0x8fffffffffffffff);
+Warnings:
+Warning	1264	Out of range value for column 'a' at row 1
+Warning	1264	Out of range value for column 'b' at row 1
+Warning	1264	Out of range value for column 'a' at row 2
+Warning	1264	Out of range value for column 'b' at row 2
+Warning	1264	Out of range value for column 'b' at row 3
+select hex(a), hex(b) from t1;
+hex(a)	hex(b)
+FFFFFFFFFFFFFFFF	7FFFFFFFFFFFFFFF
+FFFFFFFFFFFFFFFF	7FFFFFFFFFFFFFFF
+8FFFFFFFFFFFFFFF	7FFFFFFFFFFFFFFF
+drop table t1;
+CREATE TABLE t1 (c0 int);
+CREATE TABLE t2 (c0 int);
+INSERT INTO t1 VALUES(@@connect_timeout);
+INSERT INTO t2 VALUES(@@connect_timeout);
+SELECT * FROM t1 JOIN t2 ON t1.c0 = t2.c0 WHERE (t1.c0 <=> @@connect_timeout);
+c0	c0
+X	X
+DROP TABLE t1, t2;
+End of 4.1 tests
+CREATE TABLE t1 ( 
+K2C4 varchar(4) character set latin1 collate latin1_bin NOT NULL default '', 
+K4N4 varchar(4) character set latin1 collate latin1_bin NOT NULL default '0000', 
+F2I4 int(11) NOT NULL default '0' 
+) ENGINE=MyISAM DEFAULT CHARSET=latin1;
+INSERT INTO t1 VALUES 
+('W%RT', '0100',  1), 
+('W-RT', '0100', 1), 
+('WART', '0100', 1), 
+('WART', '0200', 1), 
+('WERT', '0100', 2), 
+('WORT','0200', 2), 
+('WT', '0100', 2), 
+('W_RT', '0100', 2), 
+('WaRT', '0100', 3), 
+('WART', '0300', 3), 
+('WRT' , '0400', 3), 
+('WURM', '0500', 3), 
+('W%T', '0600', 4), 
+('WA%T', '0700', 4), 
+('WA_T', '0800', 4);
+SELECT K2C4, K4N4, F2I4 FROM t1
+WHERE  K2C4 = 'WART' AND 
+(F2I4 = 2 AND K2C4 = 'WART' OR (F2I4 = 2 OR K4N4 = '0200'));
+K2C4	K4N4	F2I4
+WART	0200	1
+SELECT K2C4, K4N4, F2I4 FROM t1
+WHERE  K2C4 = 'WART' AND (K2C4 = 'WART' OR K4N4 = '0200');
+K2C4	K4N4	F2I4
+WART	0100	1
+WART	0200	1
+WART	0300	3
+DROP TABLE t1;
+create table t1 (a int, b int);
+create table t2 like t1;
+select t1.a from (t1 inner join t2 on t1.a=t2.a) where t2.a=1;
+a
+select t1.a from ((t1 inner join t2 on t1.a=t2.a)) where t2.a=1;
+a
+select x.a, y.a, z.a from ( (t1 x inner join t2 y on x.a=y.a) inner join t2 z on y.a=z.a) WHERE x.a=1;
+a	a	a
+drop table t1,t2;
+create table t1 (s1 varchar(5));
+insert into t1 values ('Wall');
+select min(s1) from t1 group by s1 with rollup;
+min(s1)
+Wall
+Wall
+drop table t1;
+create table t1 (s1 int) engine=myisam;
+insert into t1 values (0);
+select avg(distinct s1) from t1 group by s1 with rollup;
+avg(distinct s1)
+0.0000
+0.0000
+drop table t1;
+create table t1 (s1 int);
+insert into t1 values (null),(1);
+select distinct avg(s1) as x from t1 group by s1 with rollup;
+x
+NULL
+1.0000
+drop table t1;
+CREATE TABLE t1 (a int);
+CREATE TABLE t2 (a int);
+INSERT INTO t1 VALUES (1), (2), (3), (4), (5);
+INSERT INTO t2 VALUES (2), (4), (6);
+SELECT t1.a FROM t1 STRAIGHT_JOIN t2 ON t1.a=t2.a;
+a
+2
+4
+EXPLAIN SELECT t1.a FROM t1 STRAIGHT_JOIN t2 ON t1.a=t2.a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	3	Using where; Using join buffer
+EXPLAIN SELECT t1.a FROM t1 INNER JOIN t2 ON t1.a=t2.a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	Using where; Using join buffer
+DROP TABLE t1,t2;
+select x'10' + 0, X'10' + 0, b'10' + 0, B'10' + 0;
+x'10' + 0	X'10' + 0	b'10' + 0	B'10' + 0
+16	16	2	2
+create table t1 (f1 varchar(6) default NULL, f2 int(6) primary key not null);
+create table t2 (f3 varchar(5) not null, f4 varchar(5) not null, UNIQUE KEY UKEY (f3,f4));
+insert into t1 values (" 2", 2);
+insert into t2 values (" 2", " one "),(" 2", " two ");
+select * from t1 left join t2 on f1 = f3;
+f1	f2	f3	f4
+ 2	2	 2	 one 
+ 2	2	 2	 two 
+drop table t1,t2;
+create table t1 (empnum smallint, grp int);
+create table t2 (empnum int, name char(5));
+insert into t1 values(1,1);
+insert into t2 values(1,'bob');
+create view v1 as select * from t2 inner join t1 using (empnum);
+select * from v1;
+empnum	name	grp
+1	bob	1
+drop table t1,t2;
+drop view v1;
+create table t1 (pk int primary key, b int);
+create table t2 (pk int primary key, c int);
+select pk from t1 inner join t2 using (pk);
+pk
+drop table t1,t2;
+create table t1 (s1 int, s2 char(5), s3 decimal(10));
+create view v1 as select s1, s2, 'x' as s3 from t1;
+select * from t1 natural join v1;
+s1	s2	s3
+insert into t1 values (1,'x',5);
+select * from t1 natural join v1;
+s1	s2	s3
+Warnings:
+Warning	1292	Truncated incorrect DOUBLE value: 'x'
+drop table t1;
+drop view v1;
+create table t1(a1 int);
+create table t2(a2 int);
+insert into t1 values(1),(2);
+insert into t2 values(1),(2);
+create view v2 (c) as select a1 from t1;
+select * from t1 natural left join t2;
+a1	a2
+1	1
+1	2
+2	1
+2	2
+select * from t1 natural right join t2;
+a2	a1
+1	1
+1	2
+2	1
+2	2
+select * from v2 natural left join t2;
+c	a2
+1	1
+1	2
+2	1
+2	2
+select * from v2 natural right join t2;
+a2	c
+1	1
+1	2
+2	1
+2	2
+drop table t1, t2;
+drop view v2;
+create table t1 (a int(10), t1_val int(10));
+create table t2 (b int(10), t2_val int(10));
+create table t3 (a int(10), b int(10));
+insert into t1 values (1,1),(2,2);
+insert into t2 values (1,1),(2,2),(3,3);
+insert into t3 values (1,1),(2,1),(3,1),(4,1);
+select * from t1 natural join t2 natural join t3;
+a	b	t1_val	t2_val
+1	1	1	1
+2	1	2	1
+select * from t1 natural join t3 natural join t2;
+b	a	t1_val	t2_val
+1	1	1	1
+1	2	2	1
+drop table t1, t2, t3;
+DO IFNULL(NULL, NULL);
+SELECT CAST(IFNULL(NULL, NULL) AS DECIMAL);
+CAST(IFNULL(NULL, NULL) AS DECIMAL)
+NULL
+SELECT ABS(IFNULL(NULL, NULL));
+ABS(IFNULL(NULL, NULL))
+NULL
+SELECT IFNULL(NULL, NULL);
+IFNULL(NULL, NULL)
+NULL
+SET @OLD_SQL_MODE12595=@@SQL_MODE, @@SQL_MODE='';
+SHOW LOCAL VARIABLES LIKE 'SQL_MODE';
+Variable_name	Value
+sql_mode	
+CREATE TABLE BUG_12595(a varchar(100));
+INSERT INTO BUG_12595 VALUES ('hakan%'), ('hakank'), ("ha%an");
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan\%';
+a
+hakan%
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan*%' ESCAPE '*';
+a
+hakan%
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan**%' ESCAPE '**';
+ERROR HY000: Incorrect arguments to ESCAPE
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan%' ESCAPE '';
+a
+hakan%
+hakank
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan\%' ESCAPE '';
+a
+SELECT * FROM BUG_12595 WHERE a LIKE 'ha\%an' ESCAPE 0x5c;
+a
+ha%an
+SELECT * FROM BUG_12595 WHERE a LIKE 'ha%%an' ESCAPE '%';
+a
+ha%an
+SELECT * FROM BUG_12595 WHERE a LIKE 'ha\%an' ESCAPE '\\';
+a
+ha%an
+SELECT * FROM BUG_12595 WHERE a LIKE 'ha|%an' ESCAPE '|';
+a
+ha%an
+SET @@SQL_MODE='NO_BACKSLASH_ESCAPES';
+SHOW LOCAL VARIABLES LIKE 'SQL_MODE';
+Variable_name	Value
+sql_mode	NO_BACKSLASH_ESCAPES
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan\%';
+a
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan*%' ESCAPE '*';
+a
+hakan%
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan**%' ESCAPE '**';
+ERROR HY000: Incorrect arguments to ESCAPE
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan\%' ESCAPE '\\';
+ERROR HY000: Incorrect arguments to ESCAPE
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan%' ESCAPE '';
+ERROR HY000: Incorrect arguments to ESCAPE
+SELECT * FROM BUG_12595 WHERE a LIKE 'ha\%an' ESCAPE 0x5c;
+a
+ha%an
+SELECT * FROM BUG_12595 WHERE a LIKE 'ha|%an' ESCAPE '|';
+a
+ha%an
+SELECT * FROM BUG_12595 WHERE a LIKE 'hakan\n%' ESCAPE '\n';
+ERROR HY000: Incorrect arguments to ESCAPE
+SET @@SQL_MODE=@OLD_SQL_MODE12595;
+DROP TABLE BUG_12595;
+create table t1 (a char(1));
+create table t2 (a char(1));
+insert into t1 values ('a'),('b'),('c');
+insert into t2 values ('b'),('c'),('d');
+select a from t1 natural join t2;
+a
+b
+c
+select * from t1 natural join t2 where a = 'b';
+a
+b
+drop table t1, t2;
+CREATE TABLE t1 (`id` TINYINT);
+CREATE TABLE t2 (`id` TINYINT);
+CREATE TABLE t3 (`id` TINYINT);
+INSERT INTO t1 VALUES (1),(2),(3);
+INSERT INTO t2 VALUES (2);
+INSERT INTO t3 VALUES (3);
+SELECT t1.id,t3.id FROM t1 JOIN t2 ON (t2.id=t1.id) LEFT JOIN t3 USING (id);
+ERROR 23000: Column 'id' in from clause is ambiguous
+SELECT t1.id,t3.id FROM t1 JOIN t2 ON (t2.notacolumn=t1.id) LEFT JOIN t3 USING (id);
+ERROR 23000: Column 'id' in from clause is ambiguous
+SELECT id,t3.id FROM t1 JOIN t2 ON (t2.id=t1.id) LEFT JOIN t3 USING (id);
+ERROR 23000: Column 'id' in from clause is ambiguous
+SELECT id,t3.id FROM (t1 JOIN t2 ON (t2.id=t1.id)) LEFT JOIN t3 USING (id);
+ERROR 23000: Column 'id' in from clause is ambiguous
+drop table t1, t2, t3;
+create table t1 (a int(10),b int(10));
+create table t2 (a int(10),b int(10));
+insert into t1 values (1,10),(2,20),(3,30);
+insert into t2 values (1,10);
+select * from t1 inner join t2 using (A);
+a	b	b
+1	10	10
+select * from t1 inner join t2 using (a);
+a	b	b
+1	10	10
+drop table t1, t2;
+create table t1 (a int, c int);
+create table t2 (b int);
+create table t3 (b int, a int);
+create table t4 (c int);
+insert into t1 values (1,1);
+insert into t2 values (1);
+insert into t3 values (1,1);
+insert into t4 values (1);
+select * from t1 join t2 join t3 on (t2.b = t3.b and t1.a = t3.a);
+a	c	b	b	a
+1	1	1	1	1
+select * from t1, t2 join t3 on (t2.b = t3.b and t1.a = t3.a);
+ERROR 42S22: Unknown column 't1.a' in 'on clause'
+select * from t1 join t2 join t3 join t4 on (t1.a = t4.c and t2.b = t4.c);
+a	c	b	b	a	c
+1	1	1	1	1	1
+select * from t1 join t2 join t4 using (c);
+c	a	b
+1	1	1
+drop table t1, t2, t3, t4;
+create table t1(x int, y int);
+create table t2(x int, y int);
+create table t3(x int, primary key(x));
+insert into t1 values (1, 1), (2, 1), (3, 1), (4, 3), (5, 6), (6, 6);
+insert into t2 values (1, 1), (2, 1), (3, 3), (4, 6), (5, 6);
+insert into t3 values (1), (2), (3), (4), (5);
+select t1.x, t3.x from t1, t2, t3  where t1.x = t2.x and t3.x >= t1.y and t3.x <= t2.y;
+x	x
+1	1
+2	1
+3	1
+3	2
+3	3
+4	3
+4	4
+4	5
+drop table t1,t2,t3;
+create table t1 (id char(16) not null default '', primary key  (id));
+insert into t1 values ('100'),('101'),('102');
+create table t2 (id char(16) default null);
+insert into t2 values (1);
+create view v1 as select t1.id from t1;
+create view v2 as select t2.id from t2;
+create view v3 as select (t1.id+2) as id from t1 natural left join t2;
+select t1.id from t1 left join v2 using (id);
+id
+100
+101
+102
+select t1.id from v2 right join t1 using (id);
+id
+100
+101
+102
+select t1.id from t1 left join v3 using (id);
+id
+100
+101
+102
+select * from t1 left join v2 using (id);
+id
+100
+101
+102
+select * from v2 right join t1 using (id);
+id
+100
+101
+102
+select * from t1 left join v3 using (id);
+id
+100
+101
+102
+select v1.id from v1 left join v2 using (id);
+id
+100
+101
+102
+select v1.id from v2 right join v1 using (id);
+id
+100
+101
+102
+select v1.id from v1 left join v3 using (id);
+id
+100
+101
+102
+select * from v1 left join v2 using (id);
+id
+100
+101
+102
+select * from v2 right join v1 using (id);
+id
+100
+101
+102
+select * from v1 left join v3 using (id);
+id
+100
+101
+102
+drop table t1, t2;
+drop view v1, v2, v3;
+create table t1 (id int(11) not null default '0');
+insert into t1 values (123),(191),(192);
+create table t2 (id char(16) character set utf8 not null);
+insert into t2 values ('58013'),('58014'),('58015'),('58016');
+create table t3 (a_id int(11) not null, b_id char(16) character set utf8);
+insert into t3 values (123,null),(123,null),(123,null),(123,null),(123,null),(123,'58013');
+select count(*)
+from t1 inner join (t3 left join t2 on t2.id = t3.b_id) on t1.id = t3.a_id;
+count(*)
+6
+select count(*)
+from t1 inner join (t2 right join t3 on t2.id = t3.b_id) on t1.id = t3.a_id;
+count(*)
+6
+drop table t1,t2,t3;
+create table t1 (a int);
+create table t2 (b int);
+create table t3 (c int);
+select * from t1 join t2 join t3 on (t1.a=t3.c);
+a	b	c
+select * from t1 join t2 left join t3 on (t1.a=t3.c);
+a	b	c
+select * from t1 join t2 right join t3 on (t1.a=t3.c);
+a	b	c
+select * from t1 join t2 straight_join t3 on (t1.a=t3.c);
+a	b	c
+drop table t1, t2 ,t3;
+create table t1(f1 int, f2 date);
+insert into t1 values(1,'2005-01-01'),(2,'2005-09-01'),(3,'2005-09-30'),
+(4,'2005-10-01'),(5,'2005-12-30');
+select * from t1 where f2 >= 0            order by f2;
+f1	f2
+1	2005-01-01
+2	2005-09-01
+3	2005-09-30
+4	2005-10-01
+5	2005-12-30
+select * from t1 where f2 >= '0000-00-00' order by f2;
+f1	f2
+1	2005-01-01
+2	2005-09-01
+3	2005-09-30
+4	2005-10-01
+5	2005-12-30
+select * from t1 where f2 >= '2005-09-31' order by f2;
+f1	f2
+4	2005-10-01
+5	2005-12-30
+select * from t1 where f2 >= '2005-09-3a' order by f2;
+f1	f2
+3	2005-09-30
+4	2005-10-01
+5	2005-12-30
+Warnings:
+Warning	1292	Incorrect date value: '2005-09-3a' for column 'f2' at row 1
+select * from t1 where f2 <= '2005-09-31' order by f2;
+f1	f2
+1	2005-01-01
+2	2005-09-01
+3	2005-09-30
+select * from t1 where f2 <= '2005-09-3a' order by f2;
+f1	f2
+1	2005-01-01
+2	2005-09-01
+Warnings:
+Warning	1292	Incorrect date value: '2005-09-3a' for column 'f2' at row 1
+drop table t1;
+create table t1 (f1 int, f2 int);
+insert into t1 values (1, 30), (2, 20), (3, 10);
+create algorithm=merge view v1 as select f1, f2 from t1;
+create algorithm=merge view v2 (f2, f1) as select f1, f2 from t1;
+create algorithm=merge view v3 as select t1.f1 as f2, t1.f2 as f1 from t1;
+select t1.f1 as x1, f1 from t1 order by t1.f1;
+x1	f1
+1	1
+2	2
+3	3
+select v1.f1 as x1, f1 from v1 order by v1.f1;
+x1	f1
+1	1
+2	2
+3	3
+select v2.f1 as x1, f1 from v2 order by v2.f1;
+x1	f1
+10	10
+20	20
+30	30
+select v3.f1 as x1, f1 from v3 order by v3.f1;
+x1	f1
+10	10
+20	20
+30	30
+select f1, f2, v1.f1 as x1 from v1 order by v1.f1;
+f1	f2	x1
+1	30	1
+2	20	2
+3	10	3
+select f1, f2, v2.f1 as x1 from v2 order by v2.f1;
+f1	f2	x1
+10	3	10
+20	2	20
+30	1	30
+select f1, f2, v3.f1 as x1 from v3 order by v3.f1;
+f1	f2	x1
+10	3	10
+20	2	20
+30	1	30
+drop table t1;
+drop view v1, v2, v3;
+CREATE TABLE t1(key_a int4 NOT NULL, optimus varchar(32), PRIMARY KEY(key_a));
+CREATE TABLE t2(key_a int4 NOT NULL, prime varchar(32), PRIMARY KEY(key_a));
+CREATE table t3(key_a int4 NOT NULL, key_b int4 NOT NULL, foo varchar(32),
+PRIMARY KEY(key_a,key_b));
+INSERT INTO t1 VALUES (0,'');
+INSERT INTO t1 VALUES (1,'i');
+INSERT INTO t1 VALUES (2,'j');
+INSERT INTO t1 VALUES (3,'k');
+INSERT INTO t2 VALUES (1,'r');
+INSERT INTO t2 VALUES (2,'s');
+INSERT INTO t2 VALUES (3,'t');
+INSERT INTO t3 VALUES (1,5,'x');
+INSERT INTO t3 VALUES (1,6,'y');
+INSERT INTO t3 VALUES (2,5,'xx');
+INSERT INTO t3 VALUES (2,6,'yy');
+INSERT INTO t3 VALUES (2,7,'zz');
+INSERT INTO t3 VALUES (3,5,'xxx');
+SELECT t2.key_a,foo 
+FROM t1 INNER JOIN t2 ON t1.key_a = t2.key_a
+INNER JOIN t3 ON t1.key_a = t3.key_a
+WHERE t2.key_a=2 and key_b=5;
+key_a	foo
+2	xx
+EXPLAIN SELECT t2.key_a,foo 
+FROM t1 INNER JOIN t2 ON t1.key_a = t2.key_a
+INNER JOIN t3 ON t1.key_a = t3.key_a
+WHERE t2.key_a=2 and key_b=5;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	Using index
+1	SIMPLE	t2	const	PRIMARY	PRIMARY	4	const	1	Using index
+1	SIMPLE	t3	const	PRIMARY	PRIMARY	8	const,const	1	
+SELECT t2.key_a,foo 
+FROM t1 INNER JOIN t2 ON t2.key_a = t1.key_a
+INNER JOIN t3 ON t1.key_a = t3.key_a
+WHERE t2.key_a=2 and key_b=5;
+key_a	foo
+2	xx
+EXPLAIN SELECT t2.key_a,foo 
+FROM t1 INNER JOIN t2 ON t2.key_a = t1.key_a
+INNER JOIN t3 ON t1.key_a = t3.key_a
+WHERE t2.key_a=2 and key_b=5;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	Using index
+1	SIMPLE	t2	const	PRIMARY	PRIMARY	4	const	1	Using index
+1	SIMPLE	t3	const	PRIMARY	PRIMARY	8	const,const	1	
+DROP TABLE t1,t2,t3;
+create  table t1 (f1 int);
+insert into t1 values(1),(2);
+create table t2 (f2 int, f3 int, key(f2));
+insert into t2 values(1,1),(2,2);
+create table t3 (f4 int not null);
+insert into t3 values (2),(2),(2);
+select f1,(select count(*) from t2,t3 where f2=f1 and f3=f4) as count from t1;
+f1	count
+1	0
+2	3
+drop table t1,t2,t3;
+create table t1 (f1 int unique);
+create table t2 (f2 int unique);
+create table t3 (f3 int unique);
+insert into t1 values(1),(2);
+insert into t2 values(1),(2);
+insert into t3 values(1),(NULL);
+select * from t3 where f3 is null;
+f3
+NULL
+select t2.f2 from t1 left join t2 on f1=f2 join t3 on f1=f3 where f1=1;
+f2
+1
+drop table t1,t2,t3;
+create table t1(f1 char, f2 char not null);
+insert into t1 values(null,'a');
+create table t2 (f2 char not null);
+insert into t2 values('b');
+select * from t1 left join t2 on f1=t2.f2 where t1.f2='a';
+f1	f2	f2
+NULL	a	NULL
+drop table t1,t2;
+select * from (select * left join t on f1=f2) tt;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'on f1=f2) tt' at line 1
+CREATE TABLE t1 (sku int PRIMARY KEY, pr int);
+CREATE TABLE t2 (sku int PRIMARY KEY, sppr int, name varchar(255));
+INSERT INTO t1 VALUES
+(10, 10), (20, 10), (30, 20), (40, 30), (50, 10), (60, 10);
+INSERT INTO t2 VALUES 
+(10, 10, 'aaa'), (20, 10, 'bbb'), (30, 10, 'ccc'), (40, 20, 'ddd'),
+(50, 10, 'eee'), (60, 20, 'fff'), (70, 20, 'ggg'), (80, 30, 'hhh');
+SELECT t2.sku, t2.sppr, t2.name, t1.sku, t1.pr
+FROM t2, t1 WHERE t2.sku=20 AND (t2.sku=t1.sku OR t2.sppr=t1.sku);
+sku	sppr	name	sku	pr
+20	10	bbb	10	10
+20	10	bbb	20	10
+EXPLAIN
+SELECT t2.sku, t2.sppr, t2.name, t1.sku, t1.pr
+FROM t2, t1 WHERE t2.sku=20 AND (t2.sku=t1.sku OR t2.sppr=t1.sku);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	4	NULL	2	Using where
+DROP TABLE t1,t2;
+CREATE TABLE t1 (i TINYINT UNSIGNED NOT NULL);
+INSERT t1 SET i = 0;
+UPDATE t1 SET i = -1;
+Warnings:
+Warning	1264	Out of range value for column 'i' at row 1
+SELECT * FROM t1;
+i
+0
+UPDATE t1 SET i = CAST(i - 1 AS SIGNED);
+Warnings:
+Warning	1264	Out of range value for column 'i' at row 1
+SELECT * FROM t1;
+i
+0
+UPDATE t1 SET i = i - 1;
+Warnings:
+Warning	1264	Out of range value for column 'i' at row 1
+SELECT * FROM t1;
+i
+255
+DROP TABLE t1;
+create table t1 (a int);
+insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+create table t2 (a int, b int, c int, e int, primary key(a,b,c));
+insert into t2 select A.a, B.a, C.a, C.a from t1 A, t1 B, t1 C;
+analyze table t2;
+Table	Op	Msg_type	Msg_text
+test.t2	analyze	status	OK
+select 'In next EXPLAIN, B.rows must be exactly 10:' Z;
+Z
+In next EXPLAIN, B.rows must be exactly 10:
+explain select * from t2 A, t2 B where A.a=5 and A.b=5 and A.C<5
+and B.a=5 and B.b=A.e and (B.b =1 or B.b = 3 or B.b=5);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	A	range	PRIMARY	PRIMARY	12	NULL	4	Using where
+1	SIMPLE	B	ref	PRIMARY	PRIMARY	8	const,test.A.e	10	
+drop table t1, t2;
+CREATE TABLE t1 (a int PRIMARY KEY, b int, INDEX(b));
+INSERT INTO t1 VALUES (1, 3), (9,4), (7,5), (4,5), (6,2),
+(3,1), (5,1), (8,9), (2,2), (0,9);
+CREATE TABLE t2 (c int, d int, f int, INDEX(c,f));
+INSERT INTO t2 VALUES
+(1,0,0), (1,0,1), (2,0,0), (2,0,1), (3,0,0), (4,0,1),
+(5,0,0), (5,0,1), (6,0,0), (0,0,1), (7,0,0), (7,0,1),
+(0,0,0), (0,0,1), (8,0,0), (8,0,1), (9,0,0), (9,0,1);
+EXPLAIN
+SELECT a, c, d, f FROM t1,t2 WHERE a=c AND b BETWEEN 4 AND 6;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	PRIMARY,b	b	5	NULL	3	Using where
+1	SIMPLE	t2	ref	c	c	5	test.t1.a	2	Using where
+EXPLAIN
+SELECT a, c, d, f FROM t1,t2 WHERE a=c AND b BETWEEN 4 AND 6 AND a > 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	PRIMARY,b	b	5	NULL	3	Using where
+1	SIMPLE	t2	ref	c	c	5	test.t1.a	2	Using where
+DROP TABLE t1, t2;
+create table t1 (
+a int unsigned    not null auto_increment primary key,
+b bit             not null,
+c bit             not null
+);
+create table t2 (
+a int unsigned    not null auto_increment primary key,
+b bit             not null,
+c int unsigned    not null,
+d varchar(50)
+);
+insert into t1 (b,c) values (0,1), (0,1);
+insert into t2 (b,c) values (0,1);
+select t1.a, t1.b + 0, t1.c + 0, t2.a, t2.b + 0, t2.c, t2.d
+from t1 left outer join t2 on t1.a = t2.c and t2.b <> 1
+where t1.b <> 1 order by t1.a;
+a	t1.b + 0	t1.c + 0	a	t2.b + 0	c	d
+1	0	1	1	0	1	NULL
+2	0	1	NULL	NULL	NULL	NULL
+drop table t1,t2;
+SELECT 0.9888889889 * 1.011111411911;
+0.9888889889 * 1.011111411911
+0.9998769417899202067879
+prepare stmt from 'select 1 as " a "';
+Warnings:
+Warning	1466	Leading spaces are removed from name ' a '
+execute stmt;
+a 
+1
+CREATE TABLE t1 (a int NOT NULL PRIMARY KEY, b int NOT NULL);
+INSERT INTO t1 VALUES (1,1), (2,2), (3,3), (4,4);
+CREATE TABLE t2 (c int NOT NULL, INDEX idx(c));
+INSERT INTO t2 VALUES
+(1), (1), (1), (1), (1), (1), (1), (1),
+(2), (2), (2), (2),
+(3), (3),
+(4);
+EXPLAIN SELECT b FROM t1, t2 WHERE b=c AND a=1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t2	ref	idx	idx	4	const	7	Using index
+EXPLAIN SELECT b FROM t1, t2 WHERE b=c AND a=4;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t2	ref	idx	idx	4	const	1	Using index
+DROP TABLE t1, t2;
+CREATE TABLE t1 (id int NOT NULL PRIMARY KEY, a int);
+INSERT INTO t1 VALUES (1,2), (2,NULL), (3,2);
+CREATE TABLE t2 (b int, c INT, INDEX idx1(b));
+INSERT INTO t2 VALUES (2,1), (3,2);
+CREATE TABLE t3 (d int,  e int, INDEX idx1(d));
+INSERT INTO t3 VALUES (2,10), (2,20), (1,30), (2,40), (2,50);
+EXPLAIN
+SELECT * FROM t1 LEFT JOIN t2 ON t2.b=t1.a INNER JOIN t3 ON t3.d=t1.id
+WHERE t1.id=2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t2	const	idx1	NULL	NULL	NULL	1	
+1	SIMPLE	t3	ref	idx1	idx1	5	const	3	Using where
+SELECT * FROM t1 LEFT JOIN t2 ON t2.b=t1.a INNER JOIN t3 ON t3.d=t1.id
+WHERE t1.id=2;
+id	a	b	c	d	e
+2	NULL	NULL	NULL	2	10
+2	NULL	NULL	NULL	2	20
+2	NULL	NULL	NULL	2	40
+2	NULL	NULL	NULL	2	50
+DROP TABLE t1,t2,t3;
+create table t1 (c1 varchar(1), c2 int, c3 int, c4 int, c5 int, c6 int,
+c7 int, c8 int, c9 int, fulltext key (`c1`));
+select distinct match (`c1`) against ('z') , c2, c3, c4,c5, c6,c7, c8 
+from t1 where c9=1 order by c2, c2;
+match (`c1`) against ('z')	c2	c3	c4	c5	c6	c7	c8
+drop table t1;
+CREATE TABLE t1 (pk varchar(10) PRIMARY KEY, fk varchar(16));
+CREATE TABLE t2 (pk varchar(16) PRIMARY KEY, fk varchar(10));
+INSERT INTO t1 VALUES
+('d','dddd'), ('i','iii'), ('a','aa'), ('b','bb'), ('g','gg'), 
+('e','eee'), ('c','cccc'), ('h','hhh'), ('j','jjj'), ('f','fff');
+INSERT INTO t2 VALUES
+('jjj', 'j'), ('cc','c'), ('ccc','c'), ('aaa', 'a'), ('jjjj','j'),
+('hhh','h'), ('gg','g'), ('fff','f'), ('ee','e'), ('ffff','f'),
+('bbb','b'), ('ff','f'), ('cccc','c'), ('dddd','d'), ('jj','j'),
+('aaaa','a'), ('bb','b'), ('eeee','e'), ('aa','a'), ('hh','h');
+EXPLAIN SELECT t2.* 
+FROM t1 JOIN t2 ON t2.fk=t1.pk
+WHERE t2.fk < 'c' AND t2.pk=t1.fk;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	12	NULL	3	Using where
+1	SIMPLE	t2	eq_ref	PRIMARY	PRIMARY	18	test.t1.fk	1	Using where
+EXPLAIN SELECT t2.* 
+FROM t1 JOIN t2 ON t2.fk=t1.pk 
+WHERE t2.fk BETWEEN 'a' AND 'b' AND t2.pk=t1.fk;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	12	NULL	2	Using where
+1	SIMPLE	t2	eq_ref	PRIMARY	PRIMARY	18	test.t1.fk	1	Using where
+EXPLAIN SELECT t2.* 
+FROM t1 JOIN t2 ON t2.fk=t1.pk 
+WHERE t2.fk IN ('a','b') AND t2.pk=t1.fk;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	12	NULL	2	Using where
+1	SIMPLE	t2	eq_ref	PRIMARY	PRIMARY	18	test.t1.fk	1	Using where
+DROP TABLE t1,t2;
+CREATE TABLE t1 (a int, b varchar(20) NOT NULL, PRIMARY KEY(a));
+CREATE TABLE t2 (a int, b varchar(20) NOT NULL,
+PRIMARY KEY (a), UNIQUE KEY (b));
+INSERT INTO t1 VALUES (1,'a'),(2,'b'),(3,'c');
+INSERT INTO t2 VALUES (1,'a'),(2,'b'),(3,'c');
+EXPLAIN SELECT t1.a FROM t1 LEFT JOIN t2 ON t2.b=t1.b WHERE t1.a=3;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	
+DROP TABLE t1,t2;
+CREATE TABLE t1(id int PRIMARY KEY, b int, e int);
+CREATE TABLE t2(i int, a int, INDEX si(i), INDEX ai(a));
+CREATE TABLE t3(a int PRIMARY KEY, c char(4), INDEX ci(c));
+INSERT INTO t1 VALUES 
+(1,10,19), (2,20,22), (4,41,42), (9,93,95), (7, 77,79),
+(6,63,67), (5,55,58), (3,38,39), (8,81,89);
+INSERT INTO t2 VALUES
+(21,210), (41,410), (82,820), (83,830), (84,840),
+(65,650), (51,510), (37,370), (94,940), (76,760),
+(22,220), (33,330), (40,400), (95,950), (38,380),
+(67,670), (88,880), (57,570), (96,960), (97,970);
+INSERT INTO t3 VALUES
+(210,'bb'), (950,'ii'), (400,'ab'), (500,'ee'), (220,'gg'),
+(440,'gg'), (310,'eg'), (380,'ee'), (840,'bb'), (830,'ff'),
+(230,'aa'), (960,'ii'), (410,'aa'), (510,'ee'), (290,'bb'),
+(450,'gg'), (320,'dd'), (390,'hh'), (850,'jj'), (860,'ff');
+EXPLAIN
+SELECT t3.a FROM t1,t2 FORCE INDEX (si),t3
+WHERE t1.id = 8 AND t2.i BETWEEN t1.b AND t1.e AND 
+t3.a=t2.a AND t3.c IN ('bb','ee');
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t2	range	si	si	5	NULL	4	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY,ci	PRIMARY	4	test.t2.a	1	Using where
+EXPLAIN
+SELECT t3.a FROM t1,t2,t3
+WHERE t1.id = 8 AND t2.i BETWEEN t1.b AND t1.e AND
+t3.a=t2.a AND t3.c IN ('bb','ee') ;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t2	range	si,ai	si	5	NULL	4	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY,ci	PRIMARY	4	test.t2.a	1	Using where
+EXPLAIN 
+SELECT t3.a FROM t1,t2 FORCE INDEX (si),t3
+WHERE t1.id = 8 AND (t2.i=t1.b OR t2.i=t1.e) AND t3.a=t2.a AND
+t3.c IN ('bb','ee');
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t2	range	si	si	5	NULL	2	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY,ci	PRIMARY	4	test.t2.a	1	Using where
+EXPLAIN 
+SELECT t3.a FROM t1,t2,t3
+WHERE t1.id = 8 AND (t2.i=t1.b OR t2.i=t1.e) AND t3.a=t2.a AND
+t3.c IN ('bb','ee');
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t2	range	si,ai	si	5	NULL	2	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY,ci	PRIMARY	4	test.t2.a	1	Using where
+DROP TABLE t1,t2,t3;
+CREATE TABLE t1 ( f1 int primary key, f2 int, f3 int, f4 int, f5 int, f6 int, checked_out int);
+CREATE TABLE t2 ( f11 int PRIMARY KEY );
+INSERT INTO t1 VALUES (1,1,1,0,0,0,0),(2,1,1,3,8,1,0),(3,1,1,4,12,1,0);
+INSERT INTO t2 VALUES (62);
+SELECT * FROM t1 LEFT JOIN t2 ON f11 = t1.checked_out GROUP BY f1 ORDER BY f2, f3, f4, f5 LIMIT 0, 1;
+f1	f2	f3	f4	f5	f6	checked_out	f11
+1	1	1	0	0	0	0	NULL
+DROP TABLE t1, t2;
+DROP TABLE IF EXISTS t1;
+CREATE TABLE t1(a int);
+INSERT into t1 values (1), (2), (3);
+SELECT * FROM t1 LIMIT 2, -1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-1' at line 1
+DROP TABLE t1;
+CREATE TABLE t1 (
+ID_with_null int NULL,
+ID_better int NOT NULL,
+INDEX idx1 (ID_with_null),
+INDEX idx2 (ID_better)
+);
+INSERT INTO t1 VALUES (1,1), (2,1), (null,3), (null,3), (null,3), (null,3);
+INSERT INTO t1 SELECT * FROM t1 WHERE ID_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID_with_null IS NULL;
+SELECT COUNT(*) FROM t1 WHERE ID_with_null IS NULL;
+COUNT(*)
+128
+SELECT COUNT(*) FROM t1 WHERE ID_better=1;
+COUNT(*)
+2
+EXPLAIN SELECT * FROM t1 WHERE ID_better=1 AND ID_with_null IS NULL;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+DROP INDEX idx1 ON t1;
+CREATE UNIQUE INDEX idx1 ON t1(ID_with_null);
+EXPLAIN SELECT * FROM t1 WHERE ID_better=1 AND ID_with_null IS NULL;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+DROP TABLE t1;
+CREATE TABLE t1 (
+ID1_with_null int NULL,
+ID2_with_null int NULL,
+ID_better int NOT NULL,
+INDEX idx1 (ID1_with_null, ID2_with_null),
+INDEX idx2 (ID_better)
+);
+INSERT INTO t1 VALUES (1,1,1), (2,2,1), (3,null,3), (null,3,3), (null,null,3),
+(3,null,3), (null,3,3), (null,null,3), (3,null,3), (null,3,3), (null,null,3);
+INSERT INTO t1 SELECT * FROM t1 WHERE ID1_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID2_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID1_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID2_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID1_with_null IS NULL;
+INSERT INTO t1 SELECT * FROM t1 WHERE ID2_with_null IS NULL;
+SELECT COUNT(*) FROM t1 WHERE ID1_with_null IS NULL AND ID2_with_null=3;
+COUNT(*)
+24
+SELECT COUNT(*) FROM t1 WHERE ID1_with_null=3 AND ID2_with_null IS NULL;
+COUNT(*)
+24
+SELECT COUNT(*) FROM t1 WHERE ID1_with_null IS NULL AND ID2_with_null IS NULL;
+COUNT(*)
+192
+SELECT COUNT(*) FROM t1 WHERE ID_better=1;
+COUNT(*)
+2
+EXPLAIN SELECT * FROM t1
+WHERE ID_better=1 AND ID1_with_null IS NULL AND ID2_with_null=3 ;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+EXPLAIN SELECT * FROM t1
+WHERE ID_better=1 AND ID1_with_null=3 AND ID2_with_null=3 IS NULL ;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+EXPLAIN SELECT * FROM t1
+WHERE ID_better=1 AND ID1_with_null IS NULL AND ID2_with_null IS NULL;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+DROP INDEX idx1 ON t1;
+CREATE UNIQUE INDEX idx1 ON t1(ID1_with_null,ID2_with_null);
+EXPLAIN SELECT * FROM t1
+WHERE ID_better=1 AND ID1_with_null IS NULL AND ID2_with_null=3 ;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+EXPLAIN SELECT * FROM t1
+WHERE ID_better=1 AND ID1_with_null=3 AND ID2_with_null IS NULL ;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+EXPLAIN SELECT * FROM t1
+WHERE ID_better=1 AND ID1_with_null IS NULL AND ID2_with_null IS NULL;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+EXPLAIN SELECT * FROM t1
+WHERE ID_better=1 AND ID1_with_null IS NULL AND 
+(ID2_with_null=1 OR ID2_with_null=2);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	idx1,idx2	idx2	4	const	1	Using where
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, ts TIMESTAMP, KEY ts(ts));
+INSERT INTO t1 VALUES (30,"2006-01-03 23:00:00"), (31,"2006-01-03 23:00:00");
+ANALYZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+CREATE TABLE t2 (a INT, dt1 DATETIME, dt2 DATETIME, PRIMARY KEY (a));
+INSERT INTO t2 VALUES (30, "2006-01-01 00:00:00", "2999-12-31 00:00:00");
+INSERT INTO t2 SELECT a+1,dt1,dt2 FROM t2;
+ANALYZE TABLE t2;
+Table	Op	Msg_type	Msg_text
+test.t2	analyze	status	OK
+EXPLAIN
+SELECT * FROM t1 LEFT JOIN t2 ON (t1.a=t2.a) WHERE t1.a=30
+AND t1.ts BETWEEN t2.dt1 AND t2.dt2
+AND t1.ts BETWEEN "2006-01-01" AND "2006-12-31";
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	const	PRIMARY	PRIMARY	4	const	1	
+1	SIMPLE	t1	range	ts	ts	4	NULL	1	Using where
+Warnings:
+Warning	1292	Incorrect datetime value: '2999-12-31 00:00:00' for column 'ts' at row 1
+SELECT * FROM t1 LEFT JOIN t2 ON (t1.a=t2.a) WHERE t1.a=30
+AND t1.ts BETWEEN t2.dt1 AND t2.dt2
+AND t1.ts BETWEEN "2006-01-01" AND "2006-12-31";
+a	ts	a	dt1	dt2
+30	2006-01-03 23:00:00	30	2006-01-01 00:00:00	2999-12-31 00:00:00
+Warnings:
+Warning	1292	Incorrect datetime value: '2999-12-31 00:00:00' for column 'ts' at row 1
+DROP TABLE t1,t2;
+create table t1 (a bigint unsigned);
+insert into t1 values
+(if(1, 9223372036854775808, 1)),
+(case when 1 then 9223372036854775808 else 1 end),
+(coalesce(9223372036854775808, 1));
+select * from t1;
+a
+9223372036854775808
+9223372036854775808
+9223372036854775808
+drop table t1;
+create table t1 select
+if(1, 9223372036854775808, 1) i,
+case when 1 then 9223372036854775808 else 1 end c,
+coalesce(9223372036854775808, 1) co;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `i` decimal(19,0) NOT NULL DEFAULT '0',
+  `c` decimal(19,0) NOT NULL DEFAULT '0',
+  `co` decimal(19,0) NOT NULL DEFAULT '0'
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+drop table t1;
+select 
+if(1, cast(1111111111111111111 as unsigned), 1) i,
+case when 1 then cast(1111111111111111111 as unsigned) else 1 end c,
+coalesce(cast(1111111111111111111 as unsigned), 1) co;
+i	c	co
+1111111111111111111	1111111111111111111	1111111111111111111
+CREATE TABLE t1 (name varchar(255));
+CREATE TABLE t2 (name varchar(255), n int, KEY (name(3)));
+INSERT INTO t1 VALUES ('ccc'), ('bb'), ('cc '), ('aa  '), ('aa');
+INSERT INTO t2 VALUES ('bb',1), ('aa',2), ('cc   ',3);
+INSERT INTO t2 VALUES (concat('cc ', 0x06), 4);
+INSERT INTO t2 VALUES ('cc',5), ('bb ',6), ('cc ',7);
+SELECT * FROM t2;
+name	n
+bb	1
+aa	2
+cc   	3
+cc 	4
+cc	5
+bb 	6
+cc 	7
+SELECT * FROM t2 ORDER BY name;
+name	n
+aa	2
+bb	1
+bb 	6
+cc 	4
+cc   	3
+cc	5
+cc 	7
+SELECT name, LENGTH(name), n FROM t2 ORDER BY name;
+name	LENGTH(name)	n
+aa	2	2
+bb	2	1
+bb 	3	6
+cc 	4	4
+cc   	5	3
+cc	2	5
+cc 	3	7
+EXPLAIN SELECT name, LENGTH(name), n FROM t2 WHERE name='cc ';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	name	name	6	const	3	Using where
+SELECT name, LENGTH(name), n FROM t2 WHERE name='cc ';
+name	LENGTH(name)	n
+cc   	5	3
+cc	2	5
+cc 	3	7
+EXPLAIN SELECT name , LENGTH(name), n FROM t2 WHERE name LIKE 'cc%';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	name	name	6	NULL	3	Using where
+SELECT name , LENGTH(name), n FROM t2 WHERE name LIKE 'cc%';
+name	LENGTH(name)	n
+cc   	5	3
+cc 	4	4
+cc	2	5
+cc 	3	7
+EXPLAIN SELECT name , LENGTH(name), n FROM t2 WHERE name LIKE 'cc%' ORDER BY name;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	name	name	6	NULL	3	Using where; Using filesort
+SELECT name , LENGTH(name), n FROM t2 WHERE name LIKE 'cc%' ORDER BY name;
+name	LENGTH(name)	n
+cc 	4	4
+cc   	5	3
+cc	2	5
+cc 	3	7
+EXPLAIN SELECT * FROM t1 LEFT JOIN t2 ON t1.name=t2.name;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	
+1	SIMPLE	t2	ref	name	name	6	test.t1.name	2	
+SELECT * FROM t1 LEFT JOIN t2 ON t1.name=t2.name;
+name	name	n
+ccc	NULL	NULL
+bb	bb	1
+bb	bb 	6
+cc 	cc   	3
+cc 	cc	5
+cc 	cc 	7
+aa  	aa	2
+aa	aa	2
+DROP TABLE t1,t2;
+CREATE TABLE t1 (name text);
+CREATE TABLE t2 (name text, n int, KEY (name(3)));
+INSERT INTO t1 VALUES ('ccc'), ('bb'), ('cc '), ('aa  '), ('aa');
+INSERT INTO t2 VALUES ('bb',1), ('aa',2), ('cc   ',3);
+INSERT INTO t2 VALUES (concat('cc ', 0x06), 4);
+INSERT INTO t2 VALUES ('cc',5), ('bb ',6), ('cc ',7);
+SELECT * FROM t2;
+name	n
+bb	1
+aa	2
+cc   	3
+cc 	4
+cc	5
+bb 	6
+cc 	7
+SELECT * FROM t2 ORDER BY name;
+name	n
+aa	2
+bb	1
+bb 	6
+cc 	4
+cc   	3
+cc	5
+cc 	7
+SELECT name, LENGTH(name), n FROM t2 ORDER BY name;
+name	LENGTH(name)	n
+aa	2	2
+bb	2	1
+bb 	3	6
+cc 	4	4
+cc   	5	3
+cc	2	5
+cc 	3	7
+EXPLAIN SELECT name, LENGTH(name), n FROM t2 WHERE name='cc ';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ref	name	name	6	const	3	Using where
+SELECT name, LENGTH(name), n FROM t2 WHERE name='cc ';
+name	LENGTH(name)	n
+cc   	5	3
+cc	2	5
+cc 	3	7
+EXPLAIN SELECT name , LENGTH(name), n FROM t2 WHERE name LIKE 'cc%';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	name	name	6	NULL	3	Using where
+SELECT name , LENGTH(name), n FROM t2 WHERE name LIKE 'cc%';
+name	LENGTH(name)	n
+cc   	5	3
+cc 	4	4
+cc	2	5
+cc 	3	7
+EXPLAIN SELECT name , LENGTH(name), n FROM t2 WHERE name LIKE 'cc%' ORDER BY name;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	name	name	6	NULL	3	Using where; Using filesort
+SELECT name , LENGTH(name), n FROM t2 WHERE name LIKE 'cc%' ORDER BY name;
+name	LENGTH(name)	n
+cc 	4	4
+cc   	5	3
+cc	2	5
+cc 	3	7
+EXPLAIN SELECT * FROM t1 LEFT JOIN t2 ON t1.name=t2.name;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	
+1	SIMPLE	t2	ref	name	name	6	test.t1.name	2	
+SELECT * FROM t1 LEFT JOIN t2 ON t1.name=t2.name;
+name	name	n
+ccc	NULL	NULL
+bb	bb	1
+bb	bb 	6
+cc 	cc   	3
+cc 	cc	5
+cc 	cc 	7
+aa  	aa	2
+aa	aa	2
+DROP TABLE t1,t2;
+CREATE TABLE t1 (
+access_id int NOT NULL default '0',
+name varchar(20) default NULL,
+rank int NOT NULL default '0',
+KEY idx (access_id)
+);
+CREATE TABLE t2 (
+faq_group_id int NOT NULL default '0',
+faq_id int NOT NULL default '0',
+access_id int default NULL,
+UNIQUE KEY idx1 (faq_id),
+KEY idx2 (faq_group_id,faq_id)
+);
+INSERT INTO t1 VALUES 
+(1,'Everyone',2),(2,'Help',3),(3,'Technical Support',1),(4,'Chat User',4);
+INSERT INTO t2 VALUES
+(261,265,1),(490,494,1);
+SELECT t2.faq_id 
+FROM t1 INNER JOIN t2 IGNORE INDEX (idx1)
+ON (t1.access_id = t2.access_id)
+LEFT JOIN t2 t
+ON (t.faq_group_id = t2.faq_group_id AND
+find_in_set(t.access_id, '1,4') < find_in_set(t2.access_id, '1,4'))
+WHERE
+t2.access_id IN (1,4) AND t.access_id IS NULL AND t2.faq_id in (265);
+faq_id
+265
+SELECT t2.faq_id 
+FROM t1 INNER JOIN t2
+ON (t1.access_id = t2.access_id)
+LEFT JOIN t2 t
+ON (t.faq_group_id = t2.faq_group_id AND
+find_in_set(t.access_id, '1,4') < find_in_set(t2.access_id, '1,4'))
+WHERE
+t2.access_id IN (1,4) AND t.access_id IS NULL AND t2.faq_id in (265);
+faq_id
+265
+DROP TABLE t1,t2;
+CREATE TABLE t1 (a INT, b INT, KEY inx (b,a));
+INSERT INTO t1 VALUES (1,1), (1,2), (1,3), (1,4), (1,5), (1, 6), (1,7);
+EXPLAIN SELECT COUNT(*) FROM t1 f1 INNER JOIN t1 f2
+ON ( f1.b=f2.b AND f1.a<f2.a ) 
+WHERE 1 AND f1.b NOT IN (100,2232,3343,51111);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	f1	index	inx	inx	10	NULL	7	Using where; Using index
+1	SIMPLE	f2	ref	inx	inx	5	test.f1.b	1	Using where; Using index
+DROP TABLE t1;
+CREATE TABLE t1 (c1 INT, c2 INT);
+INSERT INTO t1 VALUES (1,11), (2,22), (2,22);
+EXPLAIN SELECT c1 FROM t1 WHERE (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT COUNT(c2)))))))))))))))))))))))))))))))) > 0;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Using where
+31	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+32	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+EXPLAIN SELECT c1 FROM t1 WHERE (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT COUNT(c2))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))) > 0;
+ERROR HY000: Too high level of nesting for select
+DROP TABLE t1;
+CREATE TABLE t1 (
+c1 int(11) NOT NULL AUTO_INCREMENT,
+c2 varchar(1000) DEFAULT NULL,
+c3 bigint(20) DEFAULT NULL,
+c4 bigint(20) DEFAULT NULL,
+PRIMARY KEY (c1)
+);
+EXPLAIN EXTENDED 
+SELECT  join_2.c1  
+FROM 
+t1 AS join_0, 
+t1 AS join_1, 
+t1 AS join_2, 
+t1 AS join_3, 
+t1 AS join_4, 
+t1 AS join_5, 
+t1 AS join_6, 
+t1 AS join_7
+WHERE 
+join_0.c1=join_1.c1  AND 
+join_1.c1=join_2.c1  AND 
+join_2.c1=join_3.c1  AND 
+join_3.c1=join_4.c1  AND 
+join_4.c1=join_5.c1  AND 
+join_5.c1=join_6.c1  AND 
+join_6.c1=join_7.c1 
+OR 
+join_0.c2 < '?'  AND 
+join_1.c2 < '?'  AND
+join_2.c2 > '?'  AND
+join_2.c2 < '!'  AND
+join_3.c2 > '?'  AND 
+join_4.c2 = '?'  AND 
+join_5.c2 <> '?' AND
+join_6.c2 <> '?' AND 
+join_7.c2 >= '?' AND
+join_0.c1=join_1.c1  AND 
+join_1.c1=join_2.c1  AND 
+join_2.c1=join_3.c1  AND
+join_3.c1=join_4.c1  AND 
+join_4.c1=join_5.c1  AND 
+join_5.c1=join_6.c1  AND 
+join_6.c1=join_7.c1
+GROUP BY 
+join_3.c1,
+join_2.c1,
+join_7.c1,
+join_1.c1,
+join_0.c1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+Warnings:
+Note	1003	select '0' AS `c1` from `test`.`t1` `join_0` join `test`.`t1` `join_1` join `test`.`t1` `join_2` join `test`.`t1` `join_3` join `test`.`t1` `join_4` join `test`.`t1` `join_5` join `test`.`t1` `join_6` join `test`.`t1` `join_7` where 0 group by '0','0','0','0','0'
+SHOW WARNINGS;
+Level	Code	Message
+Note	1003	select '0' AS `c1` from `test`.`t1` `join_0` join `test`.`t1` `join_1` join `test`.`t1` `join_2` join `test`.`t1` `join_3` join `test`.`t1` `join_4` join `test`.`t1` `join_5` join `test`.`t1` `join_6` join `test`.`t1` `join_7` where 0 group by '0','0','0','0','0'
+DROP TABLE t1;
+SELECT 1 AS ` `;
+
+1
+Warnings:
+Warning	1474	Name ' ' has become ''
+SELECT 1 AS `  `;
+
+1
+Warnings:
+Warning	1474	Name '  ' has become ''
+SELECT 1 AS ` x`;
+x
+1
+Warnings:
+Warning	1466	Leading spaces are removed from name ' x'
+CREATE VIEW v1 AS SELECT 1 AS ``;
+ERROR 42000: Incorrect column name ''
+CREATE VIEW v1 AS SELECT 1 AS ` `;
+ERROR 42000: Incorrect column name ' '
+CREATE VIEW v1 AS SELECT 1 AS `  `;
+ERROR 42000: Incorrect column name '  '
+CREATE VIEW v1 AS SELECT (SELECT 1 AS `  `);
+ERROR 42000: Incorrect column name '  '
+CREATE VIEW v1 AS SELECT 1 AS ` x`;
+Warnings:
+Warning	1466	Leading spaces are removed from name ' x'
+SELECT `x` FROM v1;
+x
+1
+ALTER VIEW v1 AS SELECT 1 AS ` `;
+ERROR 42000: Incorrect column name ' '
+DROP VIEW v1;
+select str_to_date('2007-10-09','%Y-%m-%d') between '2007/10/01 00:00:00 GMT'
+                                                and '2007/10/20 00:00:00 GMT';
+str_to_date('2007-10-09','%Y-%m-%d') between '2007/10/01 00:00:00 GMT'
+                                                and '2007/10/20 00:00:00 GMT'
+1
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007/10/01 00:00:00 GMT'
+Warning	1292	Truncated incorrect datetime value: '2007/10/20 00:00:00 GMT'
+select str_to_date('2007-10-09','%Y-%m-%d') > '2007/10/01 00:00:00 GMT-6';
+str_to_date('2007-10-09','%Y-%m-%d') > '2007/10/01 00:00:00 GMT-6'
+1
+Warnings:
+Warning	1292	Truncated incorrect date value: '2007/10/01 00:00:00 GMT-6'
+select str_to_date('2007-10-09','%Y-%m-%d') <= '2007/10/2000:00:00 GMT-6';
+str_to_date('2007-10-09','%Y-%m-%d') <= '2007/10/2000:00:00 GMT-6'
+1
+Warnings:
+Warning	1292	Truncated incorrect date value: '2007/10/2000:00:00 GMT-6'
+select str_to_date('2007-10-01','%Y-%m-%d') = '2007-10-1 00:00:00 GMT-6';
+str_to_date('2007-10-01','%Y-%m-%d') = '2007-10-1 00:00:00 GMT-6'
+1
+Warnings:
+Warning	1292	Truncated incorrect date value: '2007-10-1 00:00:00 GMT-6'
+select str_to_date('2007-10-01','%Y-%m-%d') = '2007-10-01 x00:00:00 GMT-6';
+str_to_date('2007-10-01','%Y-%m-%d') = '2007-10-01 x00:00:00 GMT-6'
+1
+Warnings:
+Warning	1292	Truncated incorrect date value: '2007-10-01 x00:00:00 GMT-6'
+select str_to_date('2007-10-01','%Y-%m-%d %H:%i:%s') = '2007-10-01 00:00:00 GMT-6';
+str_to_date('2007-10-01','%Y-%m-%d %H:%i:%s') = '2007-10-01 00:00:00 GMT-6'
+1
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-01 00:00:00 GMT-6'
+select str_to_date('2007-10-01','%Y-%m-%d %H:%i:%s') = '2007-10-01 00:x00:00 GMT-6';
+str_to_date('2007-10-01','%Y-%m-%d %H:%i:%s') = '2007-10-01 00:x00:00 GMT-6'
+1
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-01 00:x00:00 GMT-6'
+select str_to_date('2007-10-01','%Y-%m-%d %H:%i:%s') = '2007-10-01 x12:34:56 GMT-6';
+str_to_date('2007-10-01','%Y-%m-%d %H:%i:%s') = '2007-10-01 x12:34:56 GMT-6'
+1
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-01 x12:34:56 GMT-6'
+select str_to_date('2007-10-01 12:34:00','%Y-%m-%d %H:%i:%s') = '2007-10-01 12:34x:56 GMT-6';
+str_to_date('2007-10-01 12:34:00','%Y-%m-%d %H:%i:%s') = '2007-10-01 12:34x:56 GMT-6'
+1
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-01 12:34x:56 GMT-6'
+select str_to_date('2007-10-01 12:34:56','%Y-%m-%d %H:%i:%s') = '2007-10-01 12:34x:56 GMT-6';
+str_to_date('2007-10-01 12:34:56','%Y-%m-%d %H:%i:%s') = '2007-10-01 12:34x:56 GMT-6'
+0
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-01 12:34x:56 GMT-6'
+select str_to_date('2007-10-01 12:34:56','%Y-%m-%d %H:%i:%s') = '2007-10-01 12:34:56';
+str_to_date('2007-10-01 12:34:56','%Y-%m-%d %H:%i:%s') = '2007-10-01 12:34:56'
+1
+select str_to_date('2007-10-01','%Y-%m-%d') = '2007-10-01 12:00:00';
+str_to_date('2007-10-01','%Y-%m-%d') = '2007-10-01 12:00:00'
+0
+select str_to_date('2007-10-01 12','%Y-%m-%d %H') = '2007-10-01 12:00:00';
+str_to_date('2007-10-01 12','%Y-%m-%d %H') = '2007-10-01 12:00:00'
+1
+select str_to_date('2007-10-01 12:34','%Y-%m-%d %H') = '2007-10-01 12:00:00';
+str_to_date('2007-10-01 12:34','%Y-%m-%d %H') = '2007-10-01 12:00:00'
+1
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-01 12:34'
+select str_to_date('2007-02-30 12:34','%Y-%m-%d %H:%i') = '2007-02-30 12:34';
+str_to_date('2007-02-30 12:34','%Y-%m-%d %H:%i') = '2007-02-30 12:34'
+1
+select str_to_date('2007-10-00 12:34','%Y-%m-%d %H:%i') = '2007-10-00 12:34';
+str_to_date('2007-10-00 12:34','%Y-%m-%d %H:%i') = '2007-10-00 12:34'
+1
+select str_to_date('2007-10-00','%Y-%m-%d') between '2007/09/01 00:00:00'
+                                                and '2007/10/20 00:00:00';
+str_to_date('2007-10-00','%Y-%m-%d') between '2007/09/01 00:00:00'
+                                                and '2007/10/20 00:00:00'
+1
+set SQL_MODE=TRADITIONAL;
+select str_to_date('2007-10-00 12:34','%Y-%m-%d %H:%i') = '2007-10-00 12:34';
+str_to_date('2007-10-00 12:34','%Y-%m-%d %H:%i') = '2007-10-00 12:34'
+0
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-00 12:34'
+select str_to_date('2007-10-01 12:34','%Y-%m-%d %H:%i') = '2007-10-00 12:34';
+str_to_date('2007-10-01 12:34','%Y-%m-%d %H:%i') = '2007-10-00 12:34'
+0
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-00 12:34'
+select str_to_date('2007-10-00 12:34','%Y-%m-%d %H:%i') = '2007-10-01 12:34';
+str_to_date('2007-10-00 12:34','%Y-%m-%d %H:%i') = '2007-10-01 12:34'
+0
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '2007-10-00 12:34:00'
+select str_to_date('2007-10-00','%Y-%m-%d') between '2007/09/01'
+                                                and '2007/10/20';
+str_to_date('2007-10-00','%Y-%m-%d') between '2007/09/01'
+                                                and '2007/10/20'
+0
+Warnings:
+Warning	1292	Incorrect datetime value: '2007-10-00' for column '2007/09/01' at row 1
+Warning	1292	Incorrect datetime value: '2007-10-00' for column '2007/10/20' at row 1
+set SQL_MODE=DEFAULT;
+select str_to_date('2007-10-00','%Y-%m-%d') between '' and '2007/10/20';
+str_to_date('2007-10-00','%Y-%m-%d') between '' and '2007/10/20'
+1
+Warnings:
+Warning	1292	Truncated incorrect datetime value: ''
+select str_to_date('','%Y-%m-%d') between '2007/10/01' and '2007/10/20';
+str_to_date('','%Y-%m-%d') between '2007/10/01' and '2007/10/20'
+0
+select str_to_date('','%Y-%m-%d %H:%i') = '2007-10-01 12:34';
+str_to_date('','%Y-%m-%d %H:%i') = '2007-10-01 12:34'
+0
+select str_to_date(NULL,'%Y-%m-%d %H:%i') = '2007-10-01 12:34';
+str_to_date(NULL,'%Y-%m-%d %H:%i') = '2007-10-01 12:34'
+NULL
+select str_to_date('2007-10-00 12:34','%Y-%m-%d %H:%i') = '';
+str_to_date('2007-10-00 12:34','%Y-%m-%d %H:%i') = ''
+0
+Warnings:
+Warning	1292	Truncated incorrect datetime value: ''
+select str_to_date('1','%Y-%m-%d') = '1';
+str_to_date('1','%Y-%m-%d') = '1'
+0
+Warnings:
+Warning	1292	Truncated incorrect date value: '1'
+select str_to_date('1','%Y-%m-%d') = '1';
+str_to_date('1','%Y-%m-%d') = '1'
+0
+Warnings:
+Warning	1292	Truncated incorrect date value: '1'
+select str_to_date('','%Y-%m-%d') = '';
+str_to_date('','%Y-%m-%d') = ''
+0
+Warnings:
+Warning	1292	Truncated incorrect date value: ''
+select str_to_date('1000-01-01','%Y-%m-%d') between '0000-00-00' and NULL;
+str_to_date('1000-01-01','%Y-%m-%d') between '0000-00-00' and NULL
+0
+select str_to_date('1000-01-01','%Y-%m-%d') between NULL and '2000-00-00';
+str_to_date('1000-01-01','%Y-%m-%d') between NULL and '2000-00-00'
+0
+select str_to_date('1000-01-01','%Y-%m-%d') between NULL and NULL;
+str_to_date('1000-01-01','%Y-%m-%d') between NULL and NULL
+0
+CREATE TABLE t1 (c11 INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY);
+CREATE TABLE t2 (c21 INT UNSIGNED NOT NULL, 
+c22 INT DEFAULT NULL, 
+KEY(c21, c22));
+CREATE TABLE t3 (c31 INT UNSIGNED NOT NULL DEFAULT 0, 
+c32 INT DEFAULT NULL, 
+c33 INT NOT NULL, 
+c34 INT UNSIGNED DEFAULT 0,
+KEY (c33, c34, c32));
+INSERT INTO t1 values (),(),(),(),();
+INSERT INTO t2 SELECT a.c11, b.c11 FROM t1 a, t1 b;
+INSERT INTO t3 VALUES (1, 1, 1, 0), 
+(2, 2, 0, 0), 
+(3, 3, 1, 0), 
+(4, 4, 0, 0), 
+(5, 5, 1, 0);
+SELECT c32 FROM t1, t2, t3 WHERE t1.c11 IN (1, 3, 5) AND 
+t3.c31 = t1.c11 AND t2.c21 = t1.c11 AND 
+t3.c33 = 1 AND t2.c22 in (1, 3) 
+ORDER BY c32;
+c32
+1
+1
+3
+3
+5
+5
+SELECT c32 FROM t1, t2, t3 WHERE t1.c11 IN (1, 3, 5) AND 
+t3.c31 = t1.c11 AND t2.c21 = t1.c11 AND 
+t3.c33 = 1 AND t2.c22 in (1, 3) 
+ORDER BY c32 DESC;
+c32
+5
+5
+3
+3
+1
+1
+DROP TABLE t1, t2, t3;
+
+#
+# Bug#30736: Row Size Too Large Error Creating a Table and
+# Inserting Data.
+#
+DROP TABLE IF EXISTS t1;
+DROP TABLE IF EXISTS t2;
+
+CREATE TABLE t1(
+c1 DECIMAL(10, 2),
+c2 FLOAT);
+
+INSERT INTO t1 VALUES (0, 1), (2, 3), (4, 5);
+
+CREATE TABLE t2(
+c3 DECIMAL(10, 2))
+SELECT
+c1 * c2 AS c3
+FROM t1;
+
+SELECT * FROM t1;
+c1	c2
+0.00	1
+2.00	3
+4.00	5
+
+SELECT * FROM t2;
+c3
+0.00
+6.00
+20.00
+
+DROP TABLE t1;
+DROP TABLE t2;
+
+CREATE TABLE t1 (c1 BIGINT NOT NULL);
+INSERT INTO t1 (c1) VALUES (1);
+SELECT * FROM t1 WHERE c1 > NULL + 1;
+c1
+DROP TABLE t1;
+
+CREATE TABLE t1 (a VARCHAR(10) NOT NULL PRIMARY KEY);
+INSERT INTO t1 (a) VALUES ('foo0'), ('bar0'), ('baz0');
+SELECT * FROM t1 WHERE a IN (CONCAT('foo', 0), 'bar');
+a
+foo0
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, b INT);
+CREATE TABLE t2 (a INT, c INT, KEY(a));
+INSERT INTO t1 VALUES (1, 1), (2, 2);
+INSERT INTO t2 VALUES (1, 1), (1, 2), (1, 3), (1, 4), (1, 5),
+(2, 1), (2, 2), (2, 3), (2, 4), (2, 5),
+(3, 1), (3, 2), (3, 3), (3, 4), (3, 5),
+(4, 1), (4, 2), (4, 3), (4, 4), (4, 5);
+FLUSH STATUS;
+SELECT DISTINCT b FROM t1 LEFT JOIN t2 USING(a) WHERE c <= 3;
+b
+1
+2
+SHOW STATUS LIKE 'Handler_read%';
+Variable_name	Value
+Handler_read_first	0
+Handler_read_key	2
+Handler_read_next	0
+Handler_read_prev	0
+Handler_read_rnd	0
+Handler_read_rnd_next	6
+DROP TABLE t1, t2;
+CREATE TABLE t1 (f1 bigint(20) NOT NULL default '0',
+f2 int(11) NOT NULL default '0',
+f3 bigint(20) NOT NULL default '0',
+f4 varchar(255) NOT NULL default '',
+PRIMARY KEY (f1),
+KEY key1 (f4),
+KEY key2 (f2));
+CREATE TABLE t2 (f1 int(11) NOT NULL default '0',
+f2 enum('A1','A2','A3') NOT NULL default 'A1',
+f3 int(11) NOT NULL default '0',
+PRIMARY KEY (f1),
+KEY key1 (f3));
+CREATE TABLE t3 (f1 bigint(20) NOT NULL default '0',
+f2 datetime NOT NULL default '1980-01-01 00:00:00',
+PRIMARY KEY (f1));
+insert into t1 values (1, 1, 1, 'abc');
+insert into t1 values (2, 1, 2, 'def');
+insert into t1 values (3, 1, 2, 'def');
+insert into t2 values (1, 'A1', 1);
+insert into t3 values (1, '1980-01-01');
+SELECT a.f3, cr.f4, count(*) count
+FROM t2 a
+STRAIGHT_JOIN t1 cr ON cr.f2 = a.f1
+LEFT JOIN
+(t1 cr2
+JOIN t3 ae2 ON cr2.f3 = ae2.f1
+) ON a.f1 = cr2.f2 AND ae2.f2 < now() - INTERVAL 7 DAY AND
+cr.f4 = cr2.f4
+GROUP BY a.f3, cr.f4;
+f3	f4	count
+1	abc	1
+1	def	2
+drop table t1, t2, t3;
+CREATE TABLE t1 (a INT KEY, b INT);
+INSERT INTO t1 VALUES (1,1), (2,2), (3,3), (4,4);
+EXPLAIN EXTENDED SELECT a, b FROM t1 WHERE a > 1 AND a = b LIMIT 2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	4	NULL	3	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where ((`test`.`t1`.`b` = `test`.`t1`.`a`) and (`test`.`t1`.`a` > 1)) limit 2
+EXPLAIN EXTENDED SELECT a, b FROM t1 WHERE a > 1 AND b = a LIMIT 2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	4	NULL	3	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where ((`test`.`t1`.`a` = `test`.`t1`.`b`) and (`test`.`t1`.`a` > 1)) limit 2
+DROP TABLE t1;
+#
+# Bug#47019: Assertion failed: 0, file .\rt_mbr.c, line 138 when 
+# forcing a spatial index
+#
+CREATE TABLE t1(a LINESTRING NOT NULL, SPATIAL KEY(a));
+INSERT INTO t1 VALUES
+(GEOMFROMTEXT('LINESTRING(-1 -1, 1 -1, -1 -1, -1 1, 1 1)')),
+(GEOMFROMTEXT('LINESTRING(-1 -1, 1 -1, -1 -1, -1 1, 1 1)'));
+EXPLAIN SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	SIMPLE	t2	ALL	a	NULL	NULL	NULL	2	
+SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2;
+1
+1
+1
+1
+1
+EXPLAIN SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2 FORCE INDEX(a);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	SIMPLE	t2	ALL	a	NULL	NULL	NULL	2	
+SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2 FORCE INDEX(a);
+1
+1
+1
+1
+1
+DROP TABLE t1;
+#
+# Bug #48291 : crash with row() operator,select into @var, and 
+#   subquery returning multiple rows
+#
+CREATE TABLE t1(a INT);
+INSERT INTO t1 VALUES (2),(3);
+# Should not crash
+SELECT 1 FROM t1 WHERE a <> 1 AND NOT
+ROW(a,a) <=> ROW((SELECT 1 FROM t1 WHERE 1=2),(SELECT 1 FROM t1))
+INTO @var0;
+ERROR 21000: Subquery returns more than 1 row
+DROP TABLE t1;
+#
+# Bug #48458: simple query tries to allocate enormous amount of
+#   memory
+#
+CREATE TABLE t1(a INT NOT NULL, b YEAR);
+INSERT INTO t1 VALUES ();
+Warnings:
+Warning	1364	Field 'a' doesn't have a default value
+CREATE TABLE t2(c INT);
+# Should not err out because of out-of-memory
+SELECT 1 FROM t2 JOIN t1 ON 1=1
+WHERE a != '1' AND NOT a >= b OR NOT ROW(b,a )<> ROW(a,a);
+1
+DROP TABLE t1,t2;
+#
+# Bug #49199: Optimizer handles incorrectly: 
+# field='const1' AND field='const2' in some cases
+
+CREATE TABLE t1(a DATETIME NOT NULL);
+INSERT INTO t1 VALUES('2001-01-01');
+SELECT * FROM t1 WHERE a='2001-01-01' AND a='2001-01-01 00:00:00';
+a
+2001-01-01 00:00:00
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a='2001-01-01' AND a='2001-01-01 00:00:00';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+Warnings:
+Note	1003	select '2001-01-01 00:00:00' AS `a` from `test`.`t1` where 1
+DROP TABLE t1;
+CREATE TABLE t1(a DATE NOT NULL);
+INSERT INTO t1 VALUES('2001-01-01');
+SELECT * FROM t1 WHERE a='2001-01-01' AND a='2001-01-01 00:00:00';
+a
+2001-01-01
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a='2001-01-01' AND a='2001-01-01 00:00:00';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+Warnings:
+Note	1003	select '2001-01-01' AS `a` from `test`.`t1` where 1
+DROP TABLE t1;
+CREATE TABLE t1(a TIMESTAMP NOT NULL);
+INSERT INTO t1 VALUES('2001-01-01');
+SELECT * FROM t1 WHERE a='2001-01-01' AND a='2001-01-01 00:00:00';
+a
+2001-01-01 00:00:00
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a='2001-01-01' AND a='2001-01-01 00:00:00';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+Warnings:
+Note	1003	select '2001-01-01 00:00:00' AS `a` from `test`.`t1` where 1
+DROP TABLE t1;
+CREATE TABLE t1(a DATETIME NOT NULL, b DATE NOT NULL);
+INSERT INTO t1 VALUES('2001-01-01', '2001-01-01');
+SELECT * FROM t1 WHERE a='2001-01-01' AND a=b AND b='2001-01-01 00:00:00';
+a	b
+2001-01-01 00:00:00	2001-01-01
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a='2001-01-01' AND a=b AND b='2001-01-01 00:00:00';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+Warnings:
+Note	1003	select '2001-01-01 00:00:00' AS `a`,'2001-01-01' AS `b` from `test`.`t1` where 1
+DROP TABLE t1;
+CREATE TABLE t1(a DATETIME NOT NULL, b VARCHAR(20) NOT NULL);
+INSERT INTO t1 VALUES('2001-01-01', '2001-01-01');
+SELECT * FROM t1 WHERE a='2001-01-01' AND a=b AND b='2001-01-01 00:00:00';
+a	b
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a='2001-01-01' AND a=b AND b='2001-01-01 00:00:00';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+Warnings:
+Note	1003	select '2001-01-01 00:00:00' AS `a`,'2001-01-01' AS `b` from `test`.`t1` where 0
+SELECT * FROM t1 WHERE a='2001-01-01 00:00:00' AND a=b AND b='2001-01-01';
+a	b
+2001-01-01 00:00:00	2001-01-01
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a='2001-01-01 00:00:00' AND a=b AND b='2001-01-01';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+Warnings:
+Note	1003	select '2001-01-01 00:00:00' AS `a`,'2001-01-01' AS `b` from `test`.`t1` where 1
+DROP TABLE t1;
+CREATE TABLE t1(a DATETIME NOT NULL, b DATE NOT NULL);
+INSERT INTO t1 VALUES('2001-01-01', '2001-01-01');
+SELECT x.a, y.a, z.a FROM t1 x 
+JOIN t1 y ON x.a=y.a 
+JOIN t1 z ON y.a=z.a 
+WHERE x.a='2001-01-01' AND z.a='2001-01-01 00:00:00';
+a	a	a
+2001-01-01 00:00:00	2001-01-01 00:00:00	2001-01-01 00:00:00
+EXPLAIN EXTENDED SELECT x.a, y.a, z.a FROM t1 x 
+JOIN t1 y ON x.a=y.a 
+JOIN t1 z ON y.a=z.a 
+WHERE x.a='2001-01-01' AND z.a='2001-01-01 00:00:00';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	x	system	NULL	NULL	NULL	NULL	1	100.00	
+1	SIMPLE	y	system	NULL	NULL	NULL	NULL	1	100.00	
+1	SIMPLE	z	system	NULL	NULL	NULL	NULL	1	100.00	
+Warnings:
+Note	1003	select '2001-01-01 00:00:00' AS `a`,'2001-01-01 00:00:00' AS `a`,'2001-01-01 00:00:00' AS `a` from `test`.`t1` `x` join `test`.`t1` `y` join `test`.`t1` `z` where 1
+DROP TABLE t1;
+#
+# Bug #49897: crash in ptr_compare when char(0) NOT NULL 
+# column is used for ORDER BY
+#
+SET @old_sort_buffer_size= @@session.sort_buffer_size;
+SET @@sort_buffer_size= 40000;
+CREATE TABLE t1(a CHAR(0) NOT NULL);
+INSERT INTO t1 VALUES (0), (0), (0);
+INSERT INTO t1 SELECT t11.a FROM t1 t11, t1 t12;
+INSERT INTO t1 SELECT t11.a FROM t1 t11, t1 t12;
+INSERT INTO t1 SELECT t11.a FROM t1 t11, t1 t12;
+EXPLAIN SELECT a FROM t1 ORDER BY a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	24492	
+SELECT a FROM t1 ORDER BY a;
+DROP TABLE t1;
+CREATE TABLE t1(a CHAR(0) NOT NULL, b CHAR(0) NOT NULL, c int);
+INSERT INTO t1 VALUES (0, 0, 0), (0, 0, 2), (0, 0, 1);
+INSERT INTO t1 SELECT t11.a, t11.b, t11.c FROM t1 t11, t1 t12;
+INSERT INTO t1 SELECT t11.a, t11.b, t11.c FROM t1 t11, t1 t12;
+INSERT INTO t1 SELECT t11.a, t11.b, t11.c FROM t1 t11, t1 t12;
+EXPLAIN SELECT a FROM t1 ORDER BY a LIMIT 5;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	24492	
+SELECT a FROM t1 ORDER BY a LIMIT 5;
+a
+
+
+
+
+
+EXPLAIN SELECT * FROM t1 ORDER BY a, b LIMIT 5;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	24492	
+SELECT * FROM t1 ORDER BY a, b LIMIT 5;
+a	b	c
+		0
+		2
+		1
+		0
+		2
+EXPLAIN SELECT * FROM t1 ORDER BY a, b, c LIMIT 5;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	24492	Using filesort
+SELECT * FROM t1 ORDER BY a, b, c LIMIT 5;
+a	b	c
+		0
+		0
+		0
+		0
+		0
+EXPLAIN SELECT * FROM t1 ORDER BY c, a LIMIT 5;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	24492	Using filesort
+SELECT * FROM t1 ORDER BY c, a LIMIT 5;
+a	b	c
+		0
+		0
+		0
+		0
+		0
+SET @@sort_buffer_size= @old_sort_buffer_size;
+DROP TABLE t1;
+End of 5.0 tests
+create table t1(a INT, KEY (a));
+INSERT INTO t1 VALUES (1),(2),(3),(4),(5);
+SELECT a FROM t1 ORDER BY a LIMIT 2;
+a
+1
+2
+SELECT a FROM t1 ORDER BY a LIMIT 2,4294967296;
+a
+3
+4
+5
+SELECT a FROM t1 ORDER BY a LIMIT 2,4294967297;
+a
+3
+4
+5
+DROP TABLE t1;
+CREATE TABLE A (date_key date);
+CREATE TABLE C (
+pk int,
+int_nokey int,
+int_key int,
+date_key date NOT NULL,
+date_nokey date,
+varchar_key varchar(1)
+);
+INSERT INTO C VALUES 
+(1,1,1,'0000-00-00',NULL,NULL),
+(1,1,1,'0000-00-00',NULL,NULL);
+SELECT 1 FROM C WHERE pk > ANY (SELECT 1 FROM C);
+1
+SELECT COUNT(DISTINCT 1) FROM C 
+WHERE date_key = (SELECT 1 FROM A WHERE C.date_key IS NULL) GROUP BY pk;
+COUNT(DISTINCT 1)
+SELECT date_nokey FROM C 
+WHERE int_key IN (SELECT 1 FROM A) 
+HAVING date_nokey = '10:41:7' 
+ORDER BY date_key;
+date_nokey
+Warnings:
+Warning	1292	Incorrect date value: '10:41:7' for column 'date_nokey' at row 1
+DROP TABLE A,C;
+CREATE TABLE t1 (a INT NOT NULL, b INT);
+INSERT INTO t1 VALUES (1, 1);
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND a=a) OR b > 2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+Warnings:
+Note	1003	select '1' AS `a`,'1' AS `b` from `test`.`t1` where 1
+SELECT * FROM t1 WHERE (a=a AND a=a) OR b > 2;
+a	b
+1	1
+DROP TABLE t1;
+CREATE TABLE t1 (a INT NOT NULL, b INT NOT NULL, c INT NOT NULL);
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND b=b AND c=c) OR b > 20;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+Warnings:
+Note	1003	select '0' AS `a`,'0' AS `b`,'0' AS `c` from `test`.`t1` where 1
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND a=a AND b=b) OR b > 20;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+Warnings:
+Note	1003	select '0' AS `a`,'0' AS `b`,'0' AS `c` from `test`.`t1` where 1
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND b=b AND a=a) OR b > 20;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+Warnings:
+Note	1003	select '0' AS `a`,'0' AS `b`,'0' AS `c` from `test`.`t1` where 1
+DROP TABLE t1;
+#
+# Bug#45266: Uninitialized variable lead to an empty result.
+#
+drop table if exists A,AA,B,BB;
+CREATE TABLE `A` (
+`pk` int(11) NOT NULL AUTO_INCREMENT,
+`date_key` date NOT NULL,
+`date_nokey` date NOT NULL,
+`datetime_key` datetime NOT NULL,
+`int_nokey` int(11) NOT NULL,
+`time_key` time NOT NULL,
+`time_nokey` time NOT NULL,
+PRIMARY KEY (`pk`),
+KEY `date_key` (`date_key`),
+KEY `time_key` (`time_key`),
+KEY `datetime_key` (`datetime_key`)
+);
+CREATE TABLE `AA` (
+`pk` int(11) NOT NULL AUTO_INCREMENT,
+`int_nokey` int(11) NOT NULL,
+`time_key` time NOT NULL,
+KEY `time_key` (`time_key`),
+PRIMARY KEY (`pk`)
+);
+CREATE TABLE `B` (
+`date_nokey` date NOT NULL,
+`date_key` date NOT NULL,
+`time_key` time NOT NULL,
+`datetime_nokey` datetime NOT NULL,
+`varchar_key` varchar(1) NOT NULL,
+KEY `date_key` (`date_key`),
+KEY `time_key` (`time_key`),
+KEY `varchar_key` (`varchar_key`)
+);
+INSERT INTO `B` VALUES ('2003-07-28','2003-07-28','15:13:38','0000-00-00 00:00:00','f'),('0000-00-00','0000-00-00','00:05:48','2004-07-02 14:34:13','x');
+CREATE TABLE `BB` (
+`pk` int(11) NOT NULL AUTO_INCREMENT,
+`int_nokey` int(11) NOT NULL,
+`date_key` date NOT NULL,
+`varchar_nokey` varchar(1) NOT NULL,
+`date_nokey` date NOT NULL,
+PRIMARY KEY (`pk`),
+KEY `date_key` (`date_key`)
+);
+INSERT INTO `BB` VALUES (10,8,'0000-00-00','i','0000-00-00'),(11,0,'2005-08-18','','2005-08-18');
+SELECT table1 . `pk` AS field1 
+FROM 
+(BB AS table1 INNER JOIN 
+(AA AS table2 STRAIGHT_JOIN A AS table3 
+ON ( table3 . `date_key` = table2 . `pk` ))
+ON ( table3 . `datetime_key` = table2 . `int_nokey` ))
+WHERE  ( table3 . `date_key` <= 4 AND table2 . `pk` = table1 . `varchar_nokey`)
+GROUP BY field1 ;
+field1
+SELECT table3 .`date_key` field1
+FROM
+B table1 LEFT JOIN B table3 JOIN
+(BB table6 JOIN A table7 ON table6 .`varchar_nokey`)
+ON table6 .`int_nokey` ON table6 .`date_key`
+  WHERE  NOT ( table1 .`varchar_key`  AND table7 .`pk`) GROUP  BY field1;
+field1
+NULL
+SELECT table4 . `time_nokey` AS field1 FROM 
+(AA AS table1 CROSS JOIN 
+(AA AS table2 STRAIGHT_JOIN 
+(B AS table3 STRAIGHT_JOIN A AS table4 
+ON ( table4 . `date_key` = table3 . `time_key` ))
+ON ( table4 . `pk` = table3 . `date_nokey` ))
+ON ( table4 . `time_key` = table3 . `datetime_nokey` ))
+WHERE  ( table4 . `time_key` < table1 . `time_key` AND
+table1 . `int_nokey` != 'f')
+GROUP BY field1  ORDER BY field1 , field1;
+field1
+SELECT table1 .`time_key` field2  FROM B table1  LEFT JOIN  BB JOIN A table5 ON table5 .`date_nokey`  ON table5 .`int_nokey` GROUP  BY field2;
+field2
+00:05:48
+15:13:38
+drop table A,AA,B,BB;
+#end of test for bug#45266
+# 
+# BUG#48052: Valgrind warning - uninitialized value in init_read_record()
+# 
+CREATE TABLE t1 (
+pk int(11) NOT NULL,
+i int(11) DEFAULT NULL,
+v varchar(1) DEFAULT NULL,
+PRIMARY KEY (pk)
+);
+INSERT INTO t1 VALUES (2,7,'m');
+INSERT INTO t1 VALUES (3,9,'m');
+SELECT  v
+FROM t1
+WHERE NOT pk > 0  
+HAVING v <= 't' 
+ORDER BY pk;
+v
+DROP TABLE t1;
+#
+# Bug#49489 Uninitialized cache led to a wrong result.
+#
+CREATE TABLE t1(c1 DOUBLE(5,4));
+INSERT INTO t1 VALUES (9.1234);
+SELECT * FROM t1 WHERE c1 < 9.12345;
+c1
+9.1234
+DROP TABLE t1;
+# End of test for bug#49489.
+#
+# Bug #49517: Inconsistent behavior while using 
+# NULLable BIGINT and INT columns in comparison
+#
+CREATE TABLE t1(a BIGINT UNSIGNED NOT NULL, b BIGINT NULL, c INT NULL);
+INSERT INTO t1 VALUES(105, NULL, NULL);
+SELECT * FROM t1 WHERE b < 102;
+a	b	c
+SELECT * FROM t1 WHERE c < 102;
+a	b	c
+SELECT * FROM t1 WHERE 102 < b;
+a	b	c
+SELECT * FROM t1 WHERE 102 < c;
+a	b	c
+DROP TABLE t1;
+End of 5.1 tests
diff --git a/mysql-test/suite/funcs_1/r/is_columns_is.result b/mysql-test/suite/funcs_1/r/is_columns_is.result
index 8308fa982be..4c7504094d1 100644
--- a/mysql-test/suite/funcs_1/r/is_columns_is.result
+++ b/mysql-test/suite/funcs_1/r/is_columns_is.result
@@ -230,6 +230,18 @@ NULL	information_schema	INNODB_TRX	trx_started	3	0000-00-00 00:00:00	NO	datetime
 NULL	information_schema	INNODB_TRX	trx_state	2		NO	varchar	13	39	NULL	NULL	utf8	utf8_general_ci	varchar(13)			select	
 NULL	information_schema	INNODB_TRX	trx_wait_started	5	NULL	YES	datetime	NULL	NULL	NULL	NULL	NULL	NULL	datetime			select	
 NULL	information_schema	INNODB_TRX	trx_weight	6	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	BLOCK_SIZE	5	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	DIRTY_BLOCKS	8	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	FULL_SIZE	4	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	KEY_CACHE_NAME	1		NO	varchar	192	576	NULL	NULL	utf8	utf8_general_ci	varchar(192)			select	
+NULL	information_schema	KEY_CACHES	PARTITIONS	2	NULL	YES	int	NULL	NULL	10	0	NULL	NULL	int(3) unsigned			select	
+NULL	information_schema	KEY_CACHES	PARTITION_NUMBER	3	NULL	YES	int	NULL	NULL	10	0	NULL	NULL	int(3) unsigned			select	
+NULL	information_schema	KEY_CACHES	READS	10	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	READ_REQUESTS	9	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	UNUSED_BLOCKS	7	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	USED_BLOCKS	6	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	WRITES	12	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
+NULL	information_schema	KEY_CACHES	WRITE_REQUESTS	11	0	NO	bigint	NULL	NULL	19	0	NULL	NULL	bigint(21) unsigned			select	
 NULL	information_schema	KEY_COLUMN_USAGE	COLUMN_NAME	7		NO	varchar	64	192	NULL	NULL	utf8	utf8_general_ci	varchar(64)			select	
 NULL	information_schema	KEY_COLUMN_USAGE	CONSTRAINT_CATALOG	1	NULL	YES	varchar	512	1536	NULL	NULL	utf8	utf8_general_ci	varchar(512)			select	
 NULL	information_schema	KEY_COLUMN_USAGE	CONSTRAINT_NAME	3		NO	varchar	64	192	NULL	NULL	utf8	utf8_general_ci	varchar(64)			select	
@@ -743,6 +755,18 @@ NULL	information_schema	INNODB_TRX	trx_wait_started	datetime	NULL	NULL	NULL	NULL
 NULL	information_schema	INNODB_TRX	trx_weight	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
 NULL	information_schema	INNODB_TRX	trx_mysql_thread_id	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
 3.0000	information_schema	INNODB_TRX	trx_query	varchar	1024	3072	utf8	utf8_general_ci	varchar(1024)
+3.0000	information_schema	KEY_CACHES	KEY_CACHE_NAME	varchar	192	576	utf8	utf8_general_ci	varchar(192)
+NULL	information_schema	KEY_CACHES	PARTITIONS	int	NULL	NULL	NULL	NULL	int(3) unsigned
+NULL	information_schema	KEY_CACHES	PARTITION_NUMBER	int	NULL	NULL	NULL	NULL	int(3) unsigned
+NULL	information_schema	KEY_CACHES	FULL_SIZE	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
+NULL	information_schema	KEY_CACHES	BLOCK_SIZE	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
+NULL	information_schema	KEY_CACHES	USED_BLOCKS	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
+NULL	information_schema	KEY_CACHES	UNUSED_BLOCKS	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
+NULL	information_schema	KEY_CACHES	DIRTY_BLOCKS	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
+NULL	information_schema	KEY_CACHES	READ_REQUESTS	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
+NULL	information_schema	KEY_CACHES	READS	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
+NULL	information_schema	KEY_CACHES	WRITE_REQUESTS	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
+NULL	information_schema	KEY_CACHES	WRITES	bigint	NULL	NULL	NULL	NULL	bigint(21) unsigned
 3.0000	information_schema	KEY_COLUMN_USAGE	CONSTRAINT_CATALOG	varchar	512	1536	utf8	utf8_general_ci	varchar(512)
 3.0000	information_schema	KEY_COLUMN_USAGE	CONSTRAINT_SCHEMA	varchar	64	192	utf8	utf8_general_ci	varchar(64)
 3.0000	information_schema	KEY_COLUMN_USAGE	CONSTRAINT_NAME	varchar	64	192	utf8	utf8_general_ci	varchar(64)
diff --git a/mysql-test/suite/funcs_1/r/is_tables_is.result b/mysql-test/suite/funcs_1/r/is_tables_is.result
index 4855c8db768..99ae94d0a45 100644
--- a/mysql-test/suite/funcs_1/r/is_tables_is.result
+++ b/mysql-test/suite/funcs_1/r/is_tables_is.result
@@ -590,6 +590,29 @@ user_comment
 Separator	-----------------------------------------------------
 TABLE_CATALOG	NULL
 TABLE_SCHEMA	information_schema
+TABLE_NAME	KEY_CACHES
+TABLE_TYPE	SYSTEM VIEW
+ENGINE	MEMORY
+VERSION	10
+ROW_FORMAT	Fixed
+TABLE_ROWS	#TBLR#
+AVG_ROW_LENGTH	#ARL#
+DATA_LENGTH	#DL#
+MAX_DATA_LENGTH	#MDL#
+INDEX_LENGTH	#IL#
+DATA_FREE	#DF#
+AUTO_INCREMENT	NULL
+CREATE_TIME	#CRT#
+UPDATE_TIME	#UT#
+CHECK_TIME	#CT#
+TABLE_COLLATION	utf8_general_ci
+CHECKSUM	NULL
+CREATE_OPTIONS	#CO#
+TABLE_COMMENT	#TC#
+user_comment	
+Separator	-----------------------------------------------------
+TABLE_CATALOG	NULL
+TABLE_SCHEMA	information_schema
 TABLE_NAME	KEY_COLUMN_USAGE
 TABLE_TYPE	SYSTEM VIEW
 ENGINE	MEMORY
@@ -1688,6 +1711,29 @@ user_comment
 Separator	-----------------------------------------------------
 TABLE_CATALOG	NULL
 TABLE_SCHEMA	information_schema
+TABLE_NAME	KEY_CACHES
+TABLE_TYPE	SYSTEM VIEW
+ENGINE	MEMORY
+VERSION	10
+ROW_FORMAT	Fixed
+TABLE_ROWS	#TBLR#
+AVG_ROW_LENGTH	#ARL#
+DATA_LENGTH	#DL#
+MAX_DATA_LENGTH	#MDL#
+INDEX_LENGTH	#IL#
+DATA_FREE	#DF#
+AUTO_INCREMENT	NULL
+CREATE_TIME	#CRT#
+UPDATE_TIME	#UT#
+CHECK_TIME	#CT#
+TABLE_COLLATION	utf8_general_ci
+CHECKSUM	NULL
+CREATE_OPTIONS	#CO#
+TABLE_COMMENT	#TC#
+user_comment	
+Separator	-----------------------------------------------------
+TABLE_CATALOG	NULL
+TABLE_SCHEMA	information_schema
 TABLE_NAME	KEY_COLUMN_USAGE
 TABLE_TYPE	SYSTEM VIEW
 ENGINE	MEMORY
diff --git a/mysql-test/suite/pbxt/r/mysqlshow.result b/mysql-test/suite/pbxt/r/mysqlshow.result
index a1abcc1f076..84986956f26 100644
--- a/mysql-test/suite/pbxt/r/mysqlshow.result
+++ b/mysql-test/suite/pbxt/r/mysqlshow.result
@@ -91,6 +91,7 @@ Database: information_schema
 | GLOBAL_STATUS                         |
 | GLOBAL_VARIABLES                      |
 | INDEX_STATISTICS                      |
+| KEY_CACHES                            |
 | KEY_COLUMN_USAGE                      |
 | PARTITIONS                            |
 | PLUGINS                               |
@@ -144,6 +145,7 @@ Database: INFORMATION_SCHEMA
 | GLOBAL_STATUS                         |
 | GLOBAL_VARIABLES                      |
 | INDEX_STATISTICS                      |
+| KEY_CACHES                            |
 | KEY_COLUMN_USAGE                      |
 | PARTITIONS                            |
 | PLUGINS                               |
diff --git a/mysql-test/t/key_cache.test b/mysql-test/t/key_cache.test
index 4c14dc96aaa..7d5e33d40de 100644
--- a/mysql-test/t/key_cache.test
+++ b/mysql-test/t/key_cache.test
@@ -1,11 +1,13 @@
 #
-# Test of multiple key caches
+# Test of multiple key caches, simple an partitioned
 #
 --disable_warnings
 drop table if exists t1, t2, t3;
 --enable_warnings
 
-SET @save_key_buffer=@@key_buffer_size;
+SET @save_key_buffer_size=@@key_buffer_size;
+SET @save_key_cache_block_size=@@key_cache_block_size;
+SET @save_key_cache_partitions=@@key_cache_partitions;
 
 SELECT @@key_buffer_size, @@small.key_buffer_size;
 
@@ -33,7 +35,7 @@ SELECT @@`default`.key_buffer_size;
 SELECT @@small.key_buffer_size;
 SELECT @@medium.key_buffer_size;
 
-SET @@global.key_buffer_size=@save_key_buffer;
+SET @@global.key_buffer_size=@save_key_buffer_size;
 
 #
 # Errors
@@ -247,3 +249,270 @@ SET GLOBAL key_cache_block_size= @bug28478_key_cache_block_size;
 DROP TABLE t1;
 
 # End of 4.1 tests
+
+#
+# Test cases for partitioned key caches
+#
+
+# Test usage of the KEY_CACHE table from information schema
+# for a simple key cache
+ 
+set global key_buffer_size=@save_key_buffer_size;
+set global key_cache_block_size=@save_key_cache_block_size;
+select @@key_buffer_size;
+select @@key_cache_block_size;
+select @@key_cache_partitions;
+
+create table t1 (
+  p int not null auto_increment primary key,
+  a char(10));
+create table t2 (
+  p int  not null auto_increment primary key,
+  i int, a char(10), key k1(i), key k2(a));
+
+select @@key_cache_partitions;
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+insert into t1 values (1, 'qqqq'), (2, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+                      (3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+select * from t2;
+update t1 set p=3 where p=1;
+update t2 set i=2 where i=1;
+
+--replace_result 1808 KEY_BLOCKS_UNUSED 1670 KEY_BLOCKS_UNUSED 
+show status like 'key_%';
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+delete from t2 where a='zzzz';
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+delete from t1;
+delete from t2;
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+# For the key cache with 2 partitions execute the same sequence of
+# statements as for the simple cache above.
+# The statistical information on the number of i/o requests and
+# the number of is expected to be the same.    
+
+set global key_cache_partitions=2;
+select @@key_cache_partitions;
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+insert into t1 values (1, 'qqqq'), (2, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+                      (3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+select * from t2;
+update t1 set p=3 where p=1;
+update t2 set i=2 where i=1;
+
+--replace_result 1808 KEY_BLOCKS_UNUSED 1670 KEY_BLOCKS_UNUSED 
+show status like 'key_%';
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+delete from t1;
+delete from t2;
+--replace_column 7 # 
+select * from information_schema.key_caches where partition_number is null;
+
+# Check that we can work with one partition with the same results
+
+set global key_cache_partitions=1;
+select @@key_cache_partitions;
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+insert into t1 values (1, 'qqqq'), (2, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+                      (3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+select * from t2;
+update t1 set p=3 where p=1;
+update t2 set i=2 where i=1;
+
+--replace_result 1808 KEY_BLOCKS_UNUSED 1670 KEY_BLOCKS_UNUSED 
+show status like 'key_%';
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+delete from t1;
+delete from t2;
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+flush tables; flush status;
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+# Switch back to 2 partitions
+
+set global key_buffer_size=32*1024;
+select @@key_buffer_size;
+set global key_cache_partitions=2;
+select @@key_cache_partitions;
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+insert into t1 values (1, 'qqqq'), (2, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+                      (3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+select * from t2;
+update t1 set p=3 where p=1;
+update t2 set i=2 where i=1;
+
+--replace_column 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+# Add more rows to tables t1 and t2 
+
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+insert into t1(a) select a from t1;
+
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+insert into t2(i,a) select i,a from t2;
+
+--replace_column 6 # 7 # 10 #
+select * from information_schema.key_caches where partition_number is null;
+
+select * from t1 where p between 1010 and 1020 ;
+select * from t2 where p between 1010 and 1020 ;
+--replace_column 6 # 7 # 10 #
+select * from information_schema.key_caches where partition_number is null;
+
+flush tables; flush status;
+update t1 set a='zzzz' where a='qqqq';
+update t2 set i=1 where i=2;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+# Now test how we can work with 7 partitions 
+
+set global keycache1.key_buffer_size=256*1024;
+select @@keycache1.key_buffer_size;
+set global keycache1.key_cache_partitions=7;
+select @@keycache1.key_cache_partitions;
+
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+--replace_column 7 #
+select * from information_schema.key_caches where key_cache_name like "key%"
+                                                  and partition_number is null;
+
+cache index t1 key (`primary`) in keycache1;
+
+explain select p from t1 where p between 1010 and 1020;
+select p from t1 where p between 1010 and 1020;
+explain select i from t2 where p between 1010 and 1020;
+select i from t2 where p between 1010 and 1020;
+explain select count(*) from t1, t2 where t1.p = t2.i;
+select count(*) from t1, t2 where t1.p = t2.i;
+
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+--replace_column 7 #
+select * from information_schema.key_caches where key_cache_name like "key%"
+                                                  and partition_number is null;
+
+cache index t2 in keycache1;
+update t2 set p=p+3000, i=2 where a='qqqq';
+--replace_column 7 #
+select * from information_schema.key_caches where key_cache_name like "key%"
+                                                  and partition_number is null;
+
+set global keycache2.key_buffer_size=1024*1024;
+cache index t2 in keycache2;
+insert into t2 values (2000, 3, 'yyyy');
+--replace_column 7 #
+select * from information_schema.key_caches where key_cache_name like "keycache2"
+                                                  and partition_number is null;
+--replace_column 7 #
+select * from information_schema.key_caches where key_cache_name like "key%" 
+                                                  and partition_number is null;
+
+cache index t2 in keycache1;
+update t2 set p=p+5000 where a='zzzz';
+select * from t2 where p between 1010 and 1020;
+explain select p from t2  where p between 1010 and 1020;
+select p from t2 where p between 1010 and 1020;
+explain select i from t2 where a='yyyy' and i=3;
+select i from t2 where a='yyyy' and i=3;
+explain select a from t2 where a='yyyy' and i=3;
+select a from t2 where a='yyyy' and i=3 ;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_cache_block_size=2*1024;
+insert into t2 values (7000, 3, 'yyyy');
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_cache_block_size=8*1024;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+insert into t2 values (8000, 3, 'yyyy');
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_buffer_size=64*1024;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_cache_block_size=2*1024;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_cache_block_size=8*1024;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_buffer_size=0;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_cache_block_size=8*1024;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_buffer_size=0;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_buffer_size=128*1024;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+set global keycache1.key_cache_block_size=1024;
+--replace_column 6 # 7 #
+select * from information_schema.key_caches where partition_number is null;
+
+drop table t1,t2;
+
+set global keycache1.key_buffer_size=0;
+set global keycache2.key_buffer_size=0;
+
+set global key_buffer_size=@save_key_buffer_size;
+set global key_cache_partitions=@save_key_cache_partitions;
+
+#End of 5.1 tests
diff --git a/mysql-test/t/select_pkeycache-master.opt b/mysql-test/t/select_pkeycache-master.opt
new file mode 100644
index 00000000000..b4ba5b8ca5d
--- /dev/null
+++ b/mysql-test/t/select_pkeycache-master.opt
@@ -0,0 +1 @@
+--key_cache_partitions=7
diff --git a/mysql-test/t/select_pkeycache.test b/mysql-test/t/select_pkeycache.test
new file mode 100644
index 00000000000..4216e9a5156
--- /dev/null
+++ b/mysql-test/t/select_pkeycache.test
@@ -0,0 +1,8 @@
+
+# 
+# Run select.test partitioned default key cache (with 7 partitions)
+# (see setting the number of partitions in select_pkecache-master.opt)
+# The result is expected the same as for select.test
+#
+
+--source t/select.test
diff --git a/mysys/mf_keycache.c b/mysys/mf_keycache.c
index f7b420c3bf2..9ced597b44a 100644
--- a/mysys/mf_keycache.c
+++ b/mysys/mf_keycache.c
@@ -13,12 +13,43 @@
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
 
+
+
 /**
-  @file
+  @file 
+  The file contains the following modules:
+
+    Simple Key Cache Module
+
+    Partitioned Key Cache Module
+
+    Key Cache Interface Module
+     
+*/
+
+#include "mysys_priv.h"
+#include "mysys_err.h"
+#include <keycache.h>
+#include "my_static.h"
+#include <m_string.h>
+#include <my_bit.h>
+#include <errno.h>
+#include <stdarg.h>
+
+/****************************************************************************** 
+  Simple Key Cache Module
+
+  The module contains implementations of all key cache interface functions
+  employed by partitioned key caches. 
+     
+******************************************************************************/
+
+/*
   These functions handle keyblock cacheing for ISAM and MyISAM tables.
 
   One cache can handle many files.
   It must contain buffers of the same blocksize.
+
   init_key_cache() should be used to init cache handler.
 
   The free list (free_block_list) is a stack like structure.
@@ -37,9 +68,7 @@
   blocks_unused is the sum of never used blocks in the pool and of currently
   free blocks. blocks_used is the number of blocks fetched from the pool and
   as such gives the maximum number of in-use blocks at any time.
-*/
 
-/*
   Key Cache Locking
   =================
 
@@ -104,14 +133,77 @@
   I/O finished.
 */
 
-#include "mysys_priv.h"
-#include "mysys_err.h"
-#include <keycache.h>
-#include "my_static.h"
-#include <m_string.h>
-#include <my_bit.h>
-#include <errno.h>
-#include <stdarg.h>
+/* declare structures that is used by st_key_cache */
+
+struct st_block_link;
+typedef struct st_block_link BLOCK_LINK;
+struct st_keycache_page;
+typedef struct st_keycache_page KEYCACHE_PAGE;
+struct st_hash_link;
+typedef struct st_hash_link HASH_LINK;
+
+/* info about requests in a waiting queue */
+typedef struct st_keycache_wqueue
+{
+  struct st_my_thread_var *last_thread;  /* circular list of waiting threads */
+} KEYCACHE_WQUEUE;
+
+#define CHANGED_BLOCKS_HASH 128             /* must be power of 2 */
+
+/* Control block for a simple (non-partitioned) key cache */
+
+typedef struct st_simple_key_cache_cb
+{
+  my_bool key_cache_inited;      /* <=> control block is allocated           */            
+  my_bool in_resize;             /* true during resize operation             */
+  my_bool resize_in_flush;       /* true during flush of resize operation    */
+  my_bool can_be_used;           /* usage of cache for read/write is allowed */
+  size_t key_cache_mem_size;      /* specified size of the cache memory       */
+  uint key_cache_block_size;     /* size of the page buffer of a cache block */
+  ulong min_warm_blocks;         /* min number of warm blocks;               */
+  ulong age_threshold;           /* age threshold for hot blocks             */
+  ulonglong keycache_time;       /* total number of block link operations    */
+  uint hash_entries;             /* max number of entries in the hash table  */
+  int hash_links;                /* max number of hash links                 */
+  int hash_links_used;           /* number of hash links currently used      */
+  int disk_blocks;               /* max number of blocks in the cache        */
+  ulong blocks_used;           /* maximum number of concurrently used blocks */
+  ulong blocks_unused;           /* number of currently unused blocks        */
+  ulong blocks_changed;          /* number of currently dirty blocks         */
+  ulong warm_blocks;             /* number of blocks in warm sub-chain       */
+  ulong cnt_for_resize_op;       /* counter to block resize operation        */
+  long blocks_available;      /* number of blocks available in the LRU chain */
+  HASH_LINK **hash_root;         /* arr. of entries into hash table buckets  */
+  HASH_LINK *hash_link_root;     /* memory for hash table links              */
+  HASH_LINK *free_hash_list;     /* list of free hash links                  */
+  BLOCK_LINK *free_block_list;   /* list of free blocks */
+  BLOCK_LINK *block_root;        /* memory for block links                   */
+  uchar HUGE_PTR *block_mem;     /* memory for block buffers                 */
+  BLOCK_LINK *used_last;         /* ptr to the last block of the LRU chain   */
+  BLOCK_LINK *used_ins;          /* ptr to the insertion block in LRU chain  */
+  pthread_mutex_t cache_lock;    /* to lock access to the cache structure    */
+  KEYCACHE_WQUEUE resize_queue;  /* threads waiting during resize operation  */
+  /*
+    Waiting for a zero resize count. Using a queue for symmetry though
+    only one thread can wait here.
+  */
+  KEYCACHE_WQUEUE waiting_for_resize_cnt;
+  KEYCACHE_WQUEUE waiting_for_hash_link; /* waiting for a free hash link     */
+  KEYCACHE_WQUEUE waiting_for_block;    /* requests waiting for a free block */
+  BLOCK_LINK *changed_blocks[CHANGED_BLOCKS_HASH]; /* hash for dirty file bl.*/
+  BLOCK_LINK *file_blocks[CHANGED_BLOCKS_HASH];    /* hash for other file bl.*/
+
+  /* Statistics variables. These are reset in reset_key_cache_counters(). */
+  ulong global_blocks_changed;	/* number of currently dirty blocks         */
+  ulonglong global_cache_w_requests;/* number of write requests (write hits) */
+  ulonglong global_cache_write;     /* number of writes from cache to files  */
+  ulonglong global_cache_r_requests;/* number of read requests (read hits)   */
+  ulonglong global_cache_read;      /* number of reads from files to cache   */
+
+  int blocks;                   /* max number of blocks in the cache        */
+  uint hash_factor;             /* factor used to calculate hash function   */
+  my_bool in_init;		/* Set to 1 in MySQL during init/resize     */
+} SIMPLE_KEY_CACHE_CB;
 
 /*
   Some compilation flags have been added specifically for this module
@@ -223,7 +315,8 @@ KEY_CACHE *dflt_key_cache= &dflt_key_cache_var;
 
 #define FLUSH_CACHE         2000            /* sort this many blocks at once */
 
-static int flush_all_key_blocks(KEY_CACHE *keycache);
+static int flush_all_key_blocks(SIMPLE_KEY_CACHE_CB *keycache);
+static void end_simple_key_cache(SIMPLE_KEY_CACHE_CB *keycache, my_bool cleanup);
 #ifdef THREAD
 static void wait_on_queue(KEYCACHE_WQUEUE *wqueue,
                           pthread_mutex_t *mutex);
@@ -232,15 +325,16 @@ static void release_whole_queue(KEYCACHE_WQUEUE *wqueue);
 #define wait_on_queue(wqueue, mutex)    do {} while (0)
 #define release_whole_queue(wqueue)     do {} while (0)
 #endif
-static void free_block(KEY_CACHE *keycache, BLOCK_LINK *block);
+static void free_block(SIMPLE_KEY_CACHE_CB *keycache, BLOCK_LINK *block);
 #if !defined(DBUG_OFF)
-static void test_key_cache(KEY_CACHE *keycache,
+static void test_key_cache(SIMPLE_KEY_CACHE_CB *keycache,
                            const char *where, my_bool lock);
 #endif
-
+#define KEYCACHE_BASE_EXPR(f, pos)                                            \
+  ((ulong) ((pos) / keycache->key_cache_block_size) +	 (ulong) (f))
 #define KEYCACHE_HASH(f, pos)                                                 \
-(((ulong) ((pos) / keycache->key_cache_block_size) +                          \
-                                     (ulong) (f)) & (keycache->hash_entries-1))
+  ((KEYCACHE_BASE_EXPR(f, pos) / keycache->hash_factor) &                     \
+      (keycache->hash_entries-1))
 #define FILE_HASH(f)                 ((uint) (f) & (CHANGED_BLOCKS_HASH-1))
 
 #define DEFAULT_KEYCACHE_DEBUG_LOG  "keycache_debug.log"
@@ -336,9 +430,10 @@ static int keycache_pthread_cond_signal(pthread_cond_t *cond);
 #define inline  /* disabled inline for easier debugging */
 static int fail_block(BLOCK_LINK *block);
 static int fail_hlink(HASH_LINK *hlink);
-static int cache_empty(KEY_CACHE *keycache);
+static int cache_empty(SIMPLE_KEY_CACHE_CB *keycache);
 #endif
 
+
 static inline uint next_power(uint value)
 {
   return (uint) my_round_up_to_next_power((uint32) value) << 1;
@@ -346,19 +441,32 @@ static inline uint next_power(uint value)
 
 
 /*
-  Initialize a key cache
+  Initialize a simple key cache
 
   SYNOPSIS
-    init_key_cache()
-    keycache			pointer to a key cache data structure
-    key_cache_block_size	size of blocks to keep cached data
-    use_mem                 	total memory to use for the key cache
-    division_limit		division limit (may be zero)
-    age_threshold		age threshold (may be zero)
+    init_simple_key_cache()
+    keycache                pointer to the control block of a simple key cache 
+    key_cache_block_size    size of blocks to keep cached data
+    use_mem                 memory to use for the key cache buferrs/structures
+    division_limit          division limit (may be zero)
+    age_threshold           age threshold (may be zero)
+
+  DESCRIPTION
+    This function is the implementation of the init_key_cache interface
+    function that is employed by simple (non-partitioned) key caches.
+    The function builds a simple key cache and initializes the control block
+    structure of the type SIMPLE_KEY_CACHE_CB that is used for this key cache. 
+    The parameter keycache is supposed to point to this structure. 
+    The parameter key_cache_block_size specifies the size of the blocks in
+    the key cache to be built. The parameters division_limit and age_threshhold
+    determine the initial values of those characteristics of the key cache
+    that are used for midpoint insertion strategy. The parameter use_mem
+    specifies the total amount of memory to be allocated for key cache blocks
+    and auxiliary structures.       
 
   RETURN VALUE
     number of blocks in the key cache, if successful,
-    0 - otherwise.
+    <= 0 - otherwise.
 
   NOTES.
     if keycache->key_cache_inited != 0 we assume that the key cache
@@ -367,17 +475,17 @@ static inline uint next_power(uint value)
 
     It's assumed that no two threads call this function simultaneously
     referring to the same key cache handle.
-
 */
 
-int init_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
-                   size_t use_mem, uint division_limit,
-                   uint age_threshold)
+static
+int init_simple_key_cache(SIMPLE_KEY_CACHE_CB *keycache, uint key_cache_block_size,
+		          size_t use_mem, uint division_limit,
+		          uint age_threshold)
 {
   ulong blocks, hash_links;
   size_t length;
   int error;
-  DBUG_ENTER("init_key_cache");
+  DBUG_ENTER("init_simple_key_cache");
   DBUG_ASSERT(key_cache_block_size >= 512);
 
   KEYCACHE_DEBUG_OPEN;
@@ -387,12 +495,15 @@ int init_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
     DBUG_RETURN(0);
   }
 
+  keycache->blocks_used= keycache->blocks_unused= 0;
+  keycache->global_blocks_changed= 0;
   keycache->global_cache_w_requests= keycache->global_cache_r_requests= 0;
   keycache->global_cache_read= keycache->global_cache_write= 0;
   keycache->disk_blocks= -1;
   if (! keycache->key_cache_inited)
   {
     keycache->key_cache_inited= 1;
+    keycache->hash_factor= 1;
     /*
       Initialize these variables once only.
       Their value must survive re-initialization during resizing.
@@ -534,51 +645,42 @@ err:
 
 
 /*
-  Resize a key cache
+  Prepare for resizing a simple key cache
 
   SYNOPSIS
-    resize_key_cache()
-    keycache     	        pointer to a key cache data structure
-    key_cache_block_size        size of blocks to keep cached data
-    use_mem			total memory to use for the new key cache
-    division_limit		new division limit (if not zero)
-    age_threshold		new age threshold (if not zero)
-
-  RETURN VALUE
-    number of blocks in the key cache, if successful,
-    0 - otherwise.
+    prepare_resize_simple_key_cache()
+    keycache                pointer to the control block of a simple key cache
+    with_resize_queue       <=> resize queue is used		
+    release_lock            <=> release the key cache lock before return
 
-  NOTES.
-    The function first compares the memory size and the block size parameters
-    with the key cache values.
+  DESCRIPTION
+    This function flushes all dirty pages from a simple key cache and after
+    this it destroys the key cache calling end_simple_key_cache. The function 
+    takes the parameter keycache as a pointer to the control block 
+    structure of the type SIMPLE_KEY_CACHE_CB for this key cache.
+    The parameter with_resize_queue determines weather the resize queue is
+    involved (MySQL server never uses this queue). The parameter release_lock
+    says weather the key cache lock must be released before return from 
+    the function.
 
-    If they differ the function free the the memory allocated for the
-    old key cache blocks by calling the end_key_cache function and
-    then rebuilds the key cache with new blocks by calling
-    init_key_cache.
+  RETURN VALUE
+    0 - on success,
+    1 - otherwise.
 
-    The function starts the operation only when all other threads
-    performing operations with the key cache let her to proceed
-    (when cnt_for_resize=0).
+  NOTES
+    This function is the called by resize_simple_key_cache and
+    resize_partitioned_key_cache that resize simple and partitioned key caches
+    respectively. 
 */
 
-int resize_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
-                     size_t use_mem, uint division_limit,
-                     uint age_threshold)
+static 
+int prepare_resize_simple_key_cache(SIMPLE_KEY_CACHE_CB *keycache,
+                                    my_bool with_resize_queue,
+                                    my_bool release_lock)
 {
-  int blocks;
-  DBUG_ENTER("resize_key_cache");
-
-  if (!keycache->key_cache_inited)
-    DBUG_RETURN(keycache->disk_blocks);
-
-  if(key_cache_block_size == keycache->key_cache_block_size &&
-     use_mem == keycache->key_cache_mem_size)
-  {
-    change_key_cache_param(keycache, division_limit, age_threshold);
-    DBUG_RETURN(keycache->disk_blocks);
-  }
-
+  int res= 0;
+  DBUG_ENTER("prepare_resize_simple_key_cache"); 
+ 
   keycache_pthread_mutex_lock(&keycache->cache_lock);
 
 #ifdef THREAD
@@ -588,7 +690,7 @@ int resize_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
     one resizer only. In set_var.cc keycache->in_init is used to block
     multiple attempts.
   */
-  while (keycache->in_resize)
+  while (with_resize_queue && keycache->in_resize)
   {
     /* purecov: begin inspected */
     wait_on_queue(&keycache->resize_queue, &keycache->cache_lock);
@@ -613,8 +715,8 @@ int resize_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
     {
       /* TODO: if this happens, we should write a warning in the log file ! */
       keycache->resize_in_flush= 0;
-      blocks= 0;
       keycache->can_be_used= 0;
+      res= 1;
       goto finish;
     }
     DBUG_ASSERT(cache_empty(keycache));
@@ -640,29 +742,144 @@ int resize_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
 #else
   KEYCACHE_DBUG_ASSERT(keycache->cnt_for_resize_op == 0);
 #endif
-
-  /*
-    Free old cache structures, allocate new structures, and initialize
-    them. Note that the cache_lock mutex and the resize_queue are left
-    untouched. We do not lose the cache_lock and will release it only at
-    the end of this function.
-  */
-  end_key_cache(keycache, 0);			/* Don't free mutex */
-  /* The following will work even if use_mem is 0 */
-  blocks= init_key_cache(keycache, key_cache_block_size, use_mem,
-			 division_limit, age_threshold);
+  
+  end_simple_key_cache(keycache, 0);
 
 finish:
+  if (release_lock)
+    keycache_pthread_mutex_unlock(&keycache->cache_lock);     
+  DBUG_RETURN(res);
+}
+
+
+/*
+  Finalize resizing a simple key cache
+
+  SYNOPSIS
+    finish_resize_simple_key_cache()
+    keycache                pointer to the control block of a simple key cache
+    with_resize_queue       <=> resize queue is used		
+    acquire_lock            <=> acquire the key cache lock at start
+
+  DESCRIPTION
+    This function performs finalizing actions for the operation of 
+    resizing a simple key cache. The function takes the parameter
+    keycache as a pointer to the control block structure of the type
+    SIMPLE_KEY_CACHE_CB for this key cache. The function sets the flag
+    in_resize in this structure to FALSE.
+    The parameter with_resize_queue determines weather the resize queue
+    is involved (MySQL server never uses this queue).
+    The parameter acquire_lock says weather the key cache lock must be
+    acquired at the start of the function.
+
+  RETURN VALUE
+    none
+
+  NOTES
+    This function is the called by resize_simple_key_cache and
+    resize_partitioned_key_cache that resize simple and partitioned key caches
+    respectively. 
+*/
+
+static 
+void finish_resize_simple_key_cache(SIMPLE_KEY_CACHE_CB *keycache,
+                                    my_bool with_resize_queue,
+                                    my_bool acquire_lock)
+{
+  DBUG_ENTER("finish_resize_simple_key_cache");
+
+  if (acquire_lock)
+    keycache_pthread_mutex_lock(&keycache->cache_lock); 
+  
+  safe_mutex_assert_owner(&keycache->cache_lock);
+			   
   /*
     Mark the resize finished. This allows other threads to start a
     resize or to request new cache blocks.
   */
   keycache->in_resize= 0;
-
-  /* Signal waiting threads. */
-  release_whole_queue(&keycache->resize_queue);
+  
+  if (with_resize_queue)
+  {
+    /* Signal waiting threads. */
+    release_whole_queue(&keycache->resize_queue);
+  }
 
   keycache_pthread_mutex_unlock(&keycache->cache_lock);
+
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Resize a simple key cache
+
+  SYNOPSIS
+    resize_simple_key_cache()
+    keycache                pointer to the control block of a simple key cache
+    key_cache_block_size    size of blocks to keep cached data
+    use_mem                 memory to use for the key cache buffers/structures
+    division_limit          new division limit (if not zero)
+    age_threshold           new age threshold (if not zero)
+
+  DESCRIPTION
+    This function is the implementation of the resize_key_cache interface
+    function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type SIMPLE_KEY_CACHE_CB for the simple key
+    cache to be resized. 
+    The parameter key_cache_block_size specifies the new size of the blocks in
+    the key cache. The parameters division_limit and age_threshold
+    determine the new initial values of those characteristics of the key cache
+    that are used for midpoint insertion strategy. The parameter use_mem
+    specifies the total amount of memory to be allocated for key cache blocks
+    and auxiliary structures in the new key cache.           
+
+  RETURN VALUE
+    number of blocks in the key cache, if successful,
+    0 - otherwise.
+
+  NOTES.
+    The function first calls the function prepare_resize_simple_key_cache
+    to flush all dirty blocks from key cache, to free memory used
+    for key cache blocks and auxiliary structures. After this the
+    function builds a new key cache with new parameters.
+
+    This implementation doesn't block the calls and executions of other
+    functions from the key cache interface. However it assumes that the
+    calls of resize_simple_key_cache itself are serialized.
+
+    The function starts the operation only when all other threads
+    performing operations with the key cache let her to proceed
+    (when cnt_for_resize=0).
+*/
+
+static
+int resize_simple_key_cache(SIMPLE_KEY_CACHE_CB *keycache, uint key_cache_block_size,
+		            size_t use_mem, uint division_limit,
+		            uint age_threshold)
+{
+  int blocks= 0;
+  DBUG_ENTER("resize_simple_key_cache");
+
+  if (!keycache->key_cache_inited)
+    DBUG_RETURN(blocks);
+
+  /*
+    Note that the cache_lock mutex and the resize_queue are left untouched.
+    We do not lose the cache_lock and will release it only at the end of 
+    this function.
+  */
+  if (prepare_resize_simple_key_cache(keycache, 1, 0))
+    goto finish;
+
+  /* The following will work even if use_mem is 0 */ 
+  blocks= init_simple_key_cache(keycache, key_cache_block_size, use_mem,
+			        division_limit, age_threshold);
+
+finish:
+  finish_resize_simple_key_cache(keycache, 1, 0);
+
   DBUG_RETURN(blocks);
 }
 
@@ -670,7 +887,7 @@ finish:
 /*
   Increment counter blocking resize key cache operation
 */
-static inline void inc_counter_for_resize_op(KEY_CACHE *keycache)
+static inline void inc_counter_for_resize_op(SIMPLE_KEY_CACHE_CB *keycache)
 {
   keycache->cnt_for_resize_op++;
 }
@@ -680,35 +897,47 @@ static inline void inc_counter_for_resize_op(KEY_CACHE *keycache)
   Decrement counter blocking resize key cache operation;
   Signal the operation to proceed when counter becomes equal zero
 */
-static inline void dec_counter_for_resize_op(KEY_CACHE *keycache)
+static inline void dec_counter_for_resize_op(SIMPLE_KEY_CACHE_CB *keycache)
 {
   if (!--keycache->cnt_for_resize_op)
     release_whole_queue(&keycache->waiting_for_resize_cnt);
 }
 
+
 /*
-  Change the key cache parameters
+  Change key cache parameters of a simple key cache
 
   SYNOPSIS
-    change_key_cache_param()
-    keycache			pointer to a key cache data structure
-    division_limit		new division limit (if not zero)
-    age_threshold		new age threshold (if not zero)
+    change_simple_key_cache_param()
+    keycache                pointer to the control block of a simple key cache	
+    division_limit          new division limit (if not zero)
+    age_threshold           new age threshold (if not zero)
+
+  DESCRIPTION
+    This function is the implementation of the change_key_cache_param interface
+    function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type SIMPLE_KEY_CACHE_CB for the simple key
+    cache where new values of the division limit and the age threshold used
+    for midpoint insertion strategy are to be set.  The parameters
+    division_limit and age_threshold provide these new values.
 
   RETURN VALUE
     none
 
   NOTES.
-    Presently the function resets the key cache parameters
-    concerning midpoint insertion strategy - division_limit and
-    age_threshold.
+    Presently the function resets the key cache parameters concerning
+    midpoint insertion strategy - division_limit and age_threshold.
+    This function changes some parameters of a given key cache without
+    reformatting it. The function does not touch the contents the key 
+    cache blocks.    
 */
 
-void change_key_cache_param(KEY_CACHE *keycache, uint division_limit,
-			    uint age_threshold)
+static
+void change_simple_key_cache_param(SIMPLE_KEY_CACHE_CB *keycache, uint division_limit,
+			           uint age_threshold)
 {
-  DBUG_ENTER("change_key_cache_param");
-
+  DBUG_ENTER("change_simple_key_cache_param");
   keycache_pthread_mutex_lock(&keycache->cache_lock);
   if (division_limit)
     keycache->min_warm_blocks= (keycache->disk_blocks *
@@ -722,20 +951,31 @@ void change_key_cache_param(KEY_CACHE *keycache, uint division_limit,
 
 
 /*
-  Remove key_cache from memory
+  Destroy a simple key cache 
 
   SYNOPSIS
-    end_key_cache()
-    keycache		key cache handle
-    cleanup		Complete free (Free also mutex for key cache)
+    end_simple_key_cache()
+    keycache                pointer to the control block of a simple key cache
+    cleanup                 <=> complete free (free also mutex for key cache)
+
+  DESCRIPTION
+    This function is the implementation of the end_key_cache interface
+    function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type SIMPLE_KEY_CACHE_CB for the simple key
+    cache to be destroyed.
+    The function frees the memory allocated for the key cache blocks and
+    auxiliary structures. If the value of the parameter cleanup is TRUE 
+    then even the key cache mutex is freed.
 
   RETURN VALUE
     none
 */
 
-void end_key_cache(KEY_CACHE *keycache, my_bool cleanup)
+static
+void end_simple_key_cache(SIMPLE_KEY_CACHE_CB *keycache, my_bool cleanup)
 {
-  DBUG_ENTER("end_key_cache");
+  DBUG_ENTER("end_simple_key_cache");
   DBUG_PRINT("enter", ("key_cache: 0x%lx", (long) keycache));
 
   if (!keycache->key_cache_inited)
@@ -1026,7 +1266,7 @@ static inline void link_changed(BLOCK_LINK *block, BLOCK_LINK **phead)
     void
 */
 
-static void link_to_file_list(KEY_CACHE *keycache,
+static void link_to_file_list(SIMPLE_KEY_CACHE_CB *keycache,
                               BLOCK_LINK *block, int file,
                               my_bool unlink_block)
 {
@@ -1067,7 +1307,7 @@ static void link_to_file_list(KEY_CACHE *keycache,
     void
 */
 
-static void link_to_changed_list(KEY_CACHE *keycache,
+static void link_to_changed_list(SIMPLE_KEY_CACHE_CB *keycache,
                                  BLOCK_LINK *block)
 {
   DBUG_ASSERT(block->status & BLOCK_IN_USE);
@@ -1122,8 +1362,8 @@ static void link_to_changed_list(KEY_CACHE *keycache,
     not linked in the LRU ring.
 */
 
-static void link_block(KEY_CACHE *keycache, BLOCK_LINK *block, my_bool hot,
-                       my_bool at_end)
+static void link_block(SIMPLE_KEY_CACHE_CB *keycache, BLOCK_LINK *block,
+                       my_bool hot, my_bool at_end)
 {
   BLOCK_LINK *ins;
   BLOCK_LINK **pins;
@@ -1243,7 +1483,7 @@ static void link_block(KEY_CACHE *keycache, BLOCK_LINK *block, my_bool hot,
     See NOTES for link_block
 */
 
-static void unlink_block(KEY_CACHE *keycache, BLOCK_LINK *block)
+static void unlink_block(SIMPLE_KEY_CACHE_CB *keycache, BLOCK_LINK *block)
 {
   DBUG_ASSERT((block->status & ~BLOCK_CHANGED) == (BLOCK_READ | BLOCK_IN_USE));
   DBUG_ASSERT(block->hash_link); /*backptr to block NULL from free_block()*/
@@ -1301,7 +1541,8 @@ static void unlink_block(KEY_CACHE *keycache, BLOCK_LINK *block)
   RETURN
     void
 */
-static void reg_requests(KEY_CACHE *keycache, BLOCK_LINK *block, int count)
+static void reg_requests(SIMPLE_KEY_CACHE_CB *keycache,
+                         BLOCK_LINK *block, int count)
 {
   DBUG_ASSERT(block->status & BLOCK_IN_USE);
   DBUG_ASSERT(block->hash_link);
@@ -1344,7 +1585,7 @@ static void reg_requests(KEY_CACHE *keycache, BLOCK_LINK *block, int count)
     not linked in the LRU ring.
 */
 
-static void unreg_request(KEY_CACHE *keycache,
+static void unreg_request(SIMPLE_KEY_CACHE_CB *keycache,
                           BLOCK_LINK *block, int at_end)
 {
   DBUG_ASSERT(block->status & (BLOCK_READ | BLOCK_IN_USE));
@@ -1433,7 +1674,7 @@ static void remove_reader(BLOCK_LINK *block)
   signals on its termination
 */
 
-static void wait_for_readers(KEY_CACHE *keycache,
+static void wait_for_readers(SIMPLE_KEY_CACHE_CB *keycache,
                              BLOCK_LINK *block)
 {
 #ifdef THREAD
@@ -1482,7 +1723,7 @@ static inline void link_hash(HASH_LINK **start, HASH_LINK *hash_link)
   Remove a hash link from the hash table
 */
 
-static void unlink_hash(KEY_CACHE *keycache, HASH_LINK *hash_link)
+static void unlink_hash(SIMPLE_KEY_CACHE_CB *keycache, HASH_LINK *hash_link)
 {
   KEYCACHE_DBUG_PRINT("unlink_hash", ("fd: %u  pos_ %lu  #requests=%u",
       (uint) hash_link->file,(ulong) hash_link->diskpos, hash_link->requests));
@@ -1538,7 +1779,7 @@ static void unlink_hash(KEY_CACHE *keycache, HASH_LINK *hash_link)
   Get the hash link for a page
 */
 
-static HASH_LINK *get_hash_link(KEY_CACHE *keycache,
+static HASH_LINK *get_hash_link(SIMPLE_KEY_CACHE_CB *keycache,
                                 int file, my_off_t filepos)
 {
   reg1 HASH_LINK *hash_link, **start;
@@ -1659,7 +1900,7 @@ restart:
     waits until first of this operations links any block back.
 */
 
-static BLOCK_LINK *find_key_block(KEY_CACHE *keycache,
+static BLOCK_LINK *find_key_block(SIMPLE_KEY_CACHE_CB *keycache,
                                   File file, my_off_t filepos,
                                   int init_hits_left,
                                   int wrmode, int *page_st)
@@ -2419,7 +2660,7 @@ restart:
     portion is less than read_length, but not less than min_length.
 */
 
-static void read_block(KEY_CACHE *keycache,
+static void read_block(SIMPLE_KEY_CACHE_CB *keycache,
                        BLOCK_LINK *block, uint read_length,
                        uint min_length, my_bool primary)
 {
@@ -2507,43 +2748,60 @@ static void read_block(KEY_CACHE *keycache,
 
 
 /*
-  Read a block of data from a cached file into a buffer;
+  Read a block of data from a simple key cache into a buffer
 
   SYNOPSIS
 
-    key_cache_read()
-      keycache            pointer to a key cache data structure
-      file                handler for the file for the block of data to be read
-      filepos             position of the block of data in the file
-      level               determines the weight of the data
-      buff                buffer to where the data must be placed
-      length              length of the buffer
-      block_length        length of the block in the key cache buffer
-      return_buffer       return pointer to the key cache buffer with the data
+    simple_key_cache_read()
+    keycache            pointer to the control block of a simple key cache
+    file                handler for the file for the block of data to be read
+    filepos             position of the block of data in the file
+    level               determines the weight of the data
+    buff                buffer to where the data must be placed
+    length              length of the buffer
+    block_length        length of the read data from a key cache block 
+    return_buffer       return pointer to the key cache buffer with the data
 
+  DESCRIPTION
+    This function is the implementation of the key_cache_read interface
+    function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type SIMPLE_KEY_CACHE_CB for a simple key
+    cache.
+    In a general case the function reads a block of data from the key cache
+    into the buffer buff of the size specified by the parameter length. The
+    beginning of the  block of data to be read is specified by the parameters
+    file and filepos. The length of the read data is the same as the length
+    of the buffer. The data is read into the buffer in key_cache_block_size
+    increments. If the next portion of the data is not found in any key cache
+    block, first it is read from file into the key cache.
+    If the parameter return_buffer is not ignored and its value is TRUE, and 
+    the data to be read of the specified size block_length can be read from one
+    key cache buffer, then the function returns a pointer to the data in the
+    key cache buffer.
+    The function takse into account parameters block_length and return buffer
+    only in a single-threaded environment.
+    The parameter 'level' is used only by the midpoint insertion strategy 
+    when the data or its portion cannot be found in the key cache. 
+   
   RETURN VALUE
-    Returns address from where the data is placed if sucessful, 0 - otherwise.
+    Returns address from where the data is placed if successful, 0 - otherwise.
 
-  NOTES.
-    The function ensures that a block of data of size length from file
-    positioned at filepos is in the buffers for some key cache blocks.
-    Then the function either copies the data into the buffer buff, or,
-    if return_buffer is TRUE, it just returns the pointer to the key cache
-    buffer with the data.
+  NOTES
     Filepos must be a multiple of 'block_length', but it doesn't
     have to be a multiple of key_cache_block_size;
 */
 
-uchar *key_cache_read(KEY_CACHE *keycache,
-                      File file, my_off_t filepos, int level,
-                      uchar *buff, uint length,
-                      uint block_length __attribute__((unused)),
-                      int return_buffer __attribute__((unused)))
+uchar *simple_key_cache_read(SIMPLE_KEY_CACHE_CB *keycache,
+                             File file, my_off_t filepos, int level,
+                             uchar *buff, uint length,
+                             uint block_length __attribute__((unused)),
+                             int return_buffer __attribute__((unused)))
 {
   my_bool locked_and_incremented= FALSE;
   int error=0;
   uchar *start= buff;
-  DBUG_ENTER("key_cache_read");
+  DBUG_ENTER("simple_key_cache_read");
   DBUG_PRINT("enter", ("fd: %u  pos: %lu  length: %u",
                (uint) file, (ulong) filepos, length));
 
@@ -2738,28 +2996,47 @@ end:
 
 
 /*
-  Insert a block of file data from a buffer into key cache
+  Insert a block of file data from a buffer into a simple key cache
 
   SYNOPSIS
-    key_cache_insert()
-    keycache            pointer to a key cache data structure
+    simple_key_cache_insert()
+    keycache            pointer to the control block of a simple key cache 
     file                handler for the file to insert data from
     filepos             position of the block of data in the file to insert
     level               determines the weight of the data
     buff                buffer to read data from
     length              length of the data in the buffer
 
-  NOTES
-    This is used by MyISAM to move all blocks from a index file to the key
-    cache
-
+  DESCRIPTION
+    This function is the implementation of the key_cache_insert interface
+    function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type SIMPLE_KEY_CACHE_CB for a simple key
+    cache.
+    The function writes a block of file data from a buffer into the key cache.
+    The buffer is specified with the parameters buff and length - the pointer
+    to the beginning of the buffer and its size respectively. It's assumed
+    the buffer contains the data from 'file' allocated from the position
+    filepos. The data is copied from the buffer in key_cache_block_size
+    increments.
+    The parameter level is used to set one characteristic for the key buffers
+    loaded with the data from buff. The characteristic is used only by the
+    midpoint insertion strategy.  
+   
   RETURN VALUE
     0 if a success, 1 - otherwise.
+
+  NOTES
+    The function is used by MyISAM to move all blocks from a index file to 
+    the key cache. It can be performed in parallel with reading the file data
+    from the key buffers by other threads.
+
 */
 
-int key_cache_insert(KEY_CACHE *keycache,
-                     File file, my_off_t filepos, int level,
-                     uchar *buff, uint length)
+static
+int simple_key_cache_insert(SIMPLE_KEY_CACHE_CB *keycache,
+                            File file, my_off_t filepos, int level,
+                            uchar *buff, uint length)
 {
   int error= 0;
   DBUG_ENTER("key_cache_insert");
@@ -2979,43 +3256,64 @@ int key_cache_insert(KEY_CACHE *keycache,
 
 
 /*
-  Write a buffer into a cached file.
+  Write a buffer into a simple key cache
 
   SYNOPSIS
 
-    key_cache_write()
-      keycache            pointer to a key cache data structure
-      file                handler for the file to write data to
-      filepos             position in the file to write data to
-      level               determines the weight of the data
-      buff                buffer with the data
-      length              length of the buffer
-      dont_write          if is 0 then all dirty pages involved in writing
-                          should have been flushed from key cache
+    simple_key_cache_write()
+    keycache            pointer to the control block of a simple key cache
+    file                handler for the file to write data to
+    file_extra          maps of key cache partitions containing 
+                        dirty pages from file 
+    filepos             position in the file to write data to
+    level               determines the weight of the data
+    buff                buffer with the data
+    length              length of the buffer
+    dont_write          if is 0 then all dirty pages involved in writing
+                        should have been flushed from key cache
 
+  DESCRIPTION
+    This function is the implementation of the key_cache_write interface
+    function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type SIMPLE_KEY_CACHE_CB for a simple key
+    cache.
+    In a general case the function copies data from a buffer into the key
+    cache. The buffer is specified with the parameters buff and length -
+    the pointer to the beginning of the buffer and its size respectively.
+    It's assumed the buffer contains the data to be written into 'file'
+    starting from the position filepos. The data is copied from the buffer
+    in key_cache_block_size increments.
+    If the value of the parameter dont_write is FALSE then the function
+    also writes the data into file.
+    The parameter level is used to set one characteristic for the key buffers
+    filled with the data from buff. The characteristic is employed only by
+    the midpoint insertion strategy.
+    The parameter file_extra currently makes sense only for simple key caches
+    that are elements of a partitioned key cache. It provides a pointer to the
+    shared bitmap of the partitions that may contains dirty pages for the file.
+    This bitmap is used to optimize the function 
+    flush_partitioned_key_cache_blocks. 
+      
   RETURN VALUE
     0 if a success, 1 - otherwise.
 
-  NOTES.
-    The function copies the data of size length from buff into buffers
-    for key cache blocks that are  assigned to contain the portion of
-    the file starting with position filepos.
-    It ensures that this data is flushed to the file if dont_write is FALSE.
-    Filepos must be a multiple of 'block_length', but it doesn't
-    have to be a multiple of key_cache_block_size;
-
-    dont_write is always TRUE in the server (info->lock_type is never F_UNLCK).
+  NOTES
+    This implementation exploits the fact that the function is called only
+    when a thread has got an exclusive lock for the key file.
 */
 
-int key_cache_write(KEY_CACHE *keycache,
-                    File file, my_off_t filepos, int level,
-                    uchar *buff, uint length,
-                    uint block_length  __attribute__((unused)),
-                    int dont_write)
+static
+int simple_key_cache_write(SIMPLE_KEY_CACHE_CB *keycache,
+                           File file, void *file_extra __attribute__((unused)),                       
+                           my_off_t filepos, int level,
+                           uchar *buff, uint length,
+                           uint block_length  __attribute__((unused)),
+                           int dont_write)
 {
   my_bool locked_and_incremented= FALSE;
   int error=0;
-  DBUG_ENTER("key_cache_write");
+  DBUG_ENTER("simple_key_cache_write");
   DBUG_PRINT("enter",
              ("fd: %u  pos: %lu  length: %u  block_length: %u"
               "  key_block_length: %u",
@@ -3330,7 +3628,7 @@ end:
     Block must have a request registered on it.
 */
 
-static void free_block(KEY_CACHE *keycache, BLOCK_LINK *block)
+static void free_block(SIMPLE_KEY_CACHE_CB *keycache, BLOCK_LINK *block)
 {
   KEYCACHE_THREAD_TRACE("free block");
   KEYCACHE_DBUG_PRINT("free_block",
@@ -3470,7 +3768,7 @@ static int cmp_sec_link(BLOCK_LINK **a, BLOCK_LINK **b)
   free used blocks if requested
 */
 
-static int flush_cached_blocks(KEY_CACHE *keycache,
+static int flush_cached_blocks(SIMPLE_KEY_CACHE_CB *keycache,
                                File file, BLOCK_LINK **cache,
                                BLOCK_LINK **end,
                                enum flush_type type)
@@ -3514,9 +3812,9 @@ static int flush_cached_blocks(KEY_CACHE *keycache,
                   (BLOCK_READ | BLOCK_IN_FLUSH | BLOCK_CHANGED | BLOCK_IN_USE));
       block->status|= BLOCK_IN_FLUSHWRITE;
       keycache_pthread_mutex_unlock(&keycache->cache_lock);
-      error= my_pwrite(file, block->buffer+block->offset,
+      error= my_pwrite(file, block->buffer + block->offset,
                        block->length - block->offset,
-                       block->hash_link->diskpos+ block->offset,
+                       block->hash_link->diskpos + block->offset,
                        MYF(MY_NABP | MY_WAIT_IF_FULL));
       keycache_pthread_mutex_lock(&keycache->cache_lock);
       keycache->global_cache_write++;
@@ -3576,7 +3874,7 @@ static int flush_cached_blocks(KEY_CACHE *keycache,
 
 
 /*
-  Flush all key blocks for a file to disk, but don't do any mutex locks.
+  Flush all key blocks for a file to disk, but don't do any mutex locks
 
   SYNOPSIS
     flush_key_blocks_int()
@@ -3598,7 +3896,7 @@ static int flush_cached_blocks(KEY_CACHE *keycache,
     1  error
 */
 
-static int flush_key_blocks_int(KEY_CACHE *keycache,
+static int flush_key_blocks_int(SIMPLE_KEY_CACHE_CB *keycache,
 				File file, enum flush_type type)
 {
   BLOCK_LINK *cache_buff[FLUSH_CACHE],**cache;
@@ -4040,22 +4338,46 @@ err:
 
 
 /*
-  Flush all blocks for a file to disk
+  Flush all blocks for a file from key buffers of a simple key cache 
 
   SYNOPSIS
 
-    flush_key_blocks()
-      keycache            pointer to a key cache data structure
-      file                handler for the file to flush to
-      flush_type          type of the flush
+    flush_simple_key_blocks()
+    keycache            pointer to the control block of a simple key cache
+    file                handler for the file to flush to
+    file_extra          maps of key cache partitions containing 
+                        dirty pages from file (not used)         
+    flush_type          type of the flush operation
 
+  DESCRIPTION
+    This function is the implementation of the flush_key_blocks interface
+    function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type S_KEY_CACHE_CB for a simple key
+    cache.
+    In a general case the function flushes the data from all dirty key
+    buffers related to the file 'file' into this file. The function does
+    exactly this if the value of the parameter type is FLUSH_KEEP. If the
+    value of this parameter is FLUSH_RELEASE, the function additionally 
+    releases the key buffers containing data from 'file' for new usage.
+    If the value of the parameter type is FLUSH_IGNORE_CHANGED the function
+    just releases the key buffers containing data from 'file'.  
+    The parameter file_extra currently is not used by this function.
+      
   RETURN
     0   ok
     1  error
+
+  NOTES
+    This implementation exploits the fact that the function is called only
+    when a thread has got an exclusive lock for the key file.
 */
 
-int flush_key_blocks(KEY_CACHE *keycache,
-                     File file, enum flush_type type)
+static
+int flush_simple_key_cache_blocks(SIMPLE_KEY_CACHE_CB *keycache,
+                                  File file,
+                                  void *file_extra __attribute__((unused)),
+                                  enum flush_type type)
 {
   int res= 0;
   DBUG_ENTER("flush_key_blocks");
@@ -4109,7 +4431,7 @@ int flush_key_blocks(KEY_CACHE *keycache,
     != 0        Error
 */
 
-static int flush_all_key_blocks(KEY_CACHE *keycache)
+static int flush_all_key_blocks(SIMPLE_KEY_CACHE_CB *keycache)
 {
   BLOCK_LINK    *block;
   uint          total_found;
@@ -4212,37 +4534,43 @@ static int flush_all_key_blocks(KEY_CACHE *keycache)
 
 
 /*
-  Reset the counters of a key cache.
+  Reset the counters of a simple key cache
 
   SYNOPSIS
-    reset_key_cache_counters()
-    name       the name of a key cache
-    key_cache  pointer to the key kache to be reset
+    reset_simple_key_cache_counters()
+    name                the name of a key cache
+    keycache            pointer to the control block of a simple key cache
 
   DESCRIPTION
-   This procedure is used by process_key_caches() to reset the counters of all
-   currently used key caches, both the default one and the named ones.
+    This function is the implementation of the reset_key_cache_counters
+    interface function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type S_KEY_CACHE_CB for a simple key cache.
+    This function resets the values of all statistical counters for the key
+    cache to 0.
+    The parameter name is currently not used.
 
   RETURN
     0 on success (always because it can't fail)
 */
 
-int reset_key_cache_counters(const char *name __attribute__((unused)),
-                             KEY_CACHE *key_cache)
+static
+int reset_simple_key_cache_counters(const char *name __attribute__((unused)),
+                                    SIMPLE_KEY_CACHE_CB *keycache)
 {
-  DBUG_ENTER("reset_key_cache_counters");
-  if (!key_cache->key_cache_inited)
+  DBUG_ENTER("reset_simple_key_cache_counters");
+  if (!keycache->key_cache_inited)
   {
     DBUG_PRINT("info", ("Key cache %s not initialized.", name));
     DBUG_RETURN(0);
   }
   DBUG_PRINT("info", ("Resetting counters for key cache %s.", name));
 
-  key_cache->global_blocks_changed= 0;   /* Key_blocks_not_flushed */
-  key_cache->global_cache_r_requests= 0; /* Key_read_requests */
-  key_cache->global_cache_read= 0;       /* Key_reads */
-  key_cache->global_cache_w_requests= 0; /* Key_write_requests */
-  key_cache->global_cache_write= 0;      /* Key_writes */
+  keycache->global_blocks_changed= 0;   /* Key_blocks_not_flushed */
+  keycache->global_cache_r_requests= 0; /* Key_read_requests */
+  keycache->global_cache_read= 0;       /* Key_reads */
+  keycache->global_cache_w_requests= 0; /* Key_write_requests */
+  keycache->global_cache_write= 0;      /* Key_writes */
   DBUG_RETURN(0);
 }
 
@@ -4251,9 +4579,10 @@ int reset_key_cache_counters(const char *name __attribute__((unused)),
 /*
   Test if disk-cache is ok
 */
-static void test_key_cache(KEY_CACHE *keycache __attribute__((unused)),
-                           const char *where __attribute__((unused)),
-                           my_bool lock __attribute__((unused)))
+static
+void test_key_cache(SIMPLE_KEY_CACHE_CB *keycache __attribute__((unused)),
+                    const char *where __attribute__((unused)),
+                    my_bool lock __attribute__((unused)))
 {
   /* TODO */
 }
@@ -4265,7 +4594,7 @@ static void test_key_cache(KEY_CACHE *keycache __attribute__((unused)),
 #define MAX_QUEUE_LEN  100
 
 
-static void keycache_dump(KEY_CACHE *keycache)
+static void keycache_dump(SIMPLE_KEY_CACHE_CB *keycache)
 {
   FILE *keycache_dump_file=fopen(KEYCACHE_DUMP_FILE, "w");
   struct st_my_thread_var *last;
@@ -4505,7 +4834,7 @@ static int fail_hlink(HASH_LINK *hlink)
   return 0; /* Let the assert fail. */
 }
 
-static int cache_empty(KEY_CACHE *keycache)
+static int cache_empty(SIMPLE_KEY_CACHE_CB *keycache)
 {
   int errcnt= 0;
   int idx;
@@ -4543,3 +4872,1702 @@ static int cache_empty(KEY_CACHE *keycache)
 }
 #endif
 
+
+/*
+  Get statistics for a simple key cache
+
+  SYNOPSIS
+    get_simple_key_cache_statistics()
+    keycache            pointer to the control block of a simple key cache
+    partition_no        partition number (not used)
+    key_cache_stats OUT pointer to the structure for the returned statistics
+
+  DESCRIPTION
+    This function is the implementation of the get_key_cache_statistics
+    interface function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type SIMPLE_KEY_CACHE_CB for a simple key
+    cache. This function returns the statistical data for the key cache.
+    The parameter partition_no is not used by this function.
+
+  RETURN
+    none
+*/
+
+static
+void get_simple_key_cache_statistics(SIMPLE_KEY_CACHE_CB *keycache, 
+                                     uint partition_no __attribute__((unused)), 
+                                     KEY_CACHE_STATISTICS *keycache_stats)
+{
+  DBUG_ENTER("simple_get_key_cache_statistics");
+
+  keycache_stats->mem_size= (longlong) keycache->key_cache_mem_size;
+  keycache_stats->block_size= (longlong) keycache->key_cache_block_size;
+  keycache_stats->blocks_used= keycache->blocks_used;
+  keycache_stats->blocks_unused= keycache->blocks_unused;
+  keycache_stats->blocks_changed= keycache->global_blocks_changed;
+  keycache_stats->read_requests= keycache->global_cache_r_requests;
+  keycache_stats->reads= keycache->global_cache_read;
+  keycache_stats->write_requests= keycache->global_cache_w_requests;
+  keycache_stats->writes= keycache->global_cache_write;
+  DBUG_VOID_RETURN;  
+}
+
+
+/* 
+  Offsets of the statistical values in the control block for a simple key cache
+  The first NO_LONG_KEY_CACHE_STAT_VARIABLES=3 are of the ulong type  while the
+  remaining are of the ulonglong type.
+ */
+static size_t simple_key_cache_stat_var_offsets[]=
+{
+  offsetof(SIMPLE_KEY_CACHE_CB, blocks_used),
+  offsetof(SIMPLE_KEY_CACHE_CB, blocks_unused),
+  offsetof(SIMPLE_KEY_CACHE_CB, global_blocks_changed),
+  offsetof(SIMPLE_KEY_CACHE_CB, global_cache_w_requests),
+  offsetof(SIMPLE_KEY_CACHE_CB, global_cache_write),
+  offsetof(SIMPLE_KEY_CACHE_CB, global_cache_r_requests),
+  offsetof(SIMPLE_KEY_CACHE_CB, global_cache_read)
+};
+
+
+/*
+  Get the value of a statistical variable for a simple key cache
+
+  SYNOPSIS
+    get_simple_key_cache_stat_value()
+    keycache            pointer to the control block of a simple key cache
+    var_no              the ordered number of a statistical variable 
+
+  DESCRIPTION
+    This function is the implementation of the get_simple_key_cache_stat_value
+    interface function that is employed by simple (non-partitioned) key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type SIMPLE_KEY_CACHE_CB for a simple key
+    cache. This function returns the value of the statistical variable var_no
+    for this key cache. The variables are numbered starting from 0 to 6.
+
+  RETURN
+    The value of the specified statistical variable 
+
+*/
+
+static
+ulonglong get_simple_key_cache_stat_value(SIMPLE_KEY_CACHE_CB *keycache,
+                                          uint var_no)
+{
+  size_t var_ofs= simple_key_cache_stat_var_offsets[var_no];
+  ulonglong res= 0;
+  DBUG_ENTER("get_simple_key_cache_stat_value");
+
+  if (var_no < 3)
+    res= (ulonglong) (*(long *) ((char *) keycache + var_ofs));
+  else
+    res= *(ulonglong *) ((char *) keycache + var_ofs);
+  
+  DBUG_RETURN(res);
+}
+
+
+/* 
+  The array of pointer to the key cache interface functions used for simple
+  key caches. Any simple key cache objects including those incorporated into
+  partitioned keys caches exploit this array.
+
+  The current implementation of these functions allows to call them from 
+  the MySQL server code directly. We don't do it though. 
+*/
+   
+static KEY_CACHE_FUNCS simple_key_cache_funcs =
+{
+  (INIT_KEY_CACHE) init_simple_key_cache,
+  (RESIZE_KEY_CACHE) resize_simple_key_cache,
+  (CHANGE_KEY_CACHE_PARAM) change_simple_key_cache_param,      
+  (KEY_CACHE_READ) simple_key_cache_read,
+  (KEY_CACHE_INSERT) simple_key_cache_insert,
+  (KEY_CACHE_WRITE) simple_key_cache_write,
+  (FLUSH_KEY_BLOCKS) flush_simple_key_cache_blocks, 
+  (RESET_KEY_CACHE_COUNTERS) reset_simple_key_cache_counters, 
+  (END_KEY_CACHE) end_simple_key_cache, 
+  (GET_KEY_CACHE_STATISTICS) get_simple_key_cache_statistics,
+  (GET_KEY_CACHE_STAT_VALUE) get_simple_key_cache_stat_value
+};
+
+
+/****************************************************************************** 
+  Partitioned Key Cache Module
+
+  The module contains implementations of all key cache interface functions
+  employed by partitioned key caches. 
+
+  A partitioned key cache is a collection of structures for simple key caches
+  called key cache partitions. Any page from a file can be placed into a buffer
+  of only one partition. The number of the partition is calculated from
+  the file number and the position of the page in the file, and it's always the
+  same for the page. The function that maps pages into partitions takes care
+  of even distribution of pages among partitions.
+
+  Partition key cache mitigate one of the major problem of simple key cache:
+  thread contention for key cache lock (mutex). Every call of a key cache 
+  interface function must acquire this lock. So threads compete for this lock
+  even in the case when they have acquired shared locks for the file and
+  pages they want read from are in the key cache buffers.
+  When working with a partitioned key cache any key cache interface function
+  that needs only one page has to acquire the key cache lock only for the
+  partition the page is ascribed to. This makes the chances for threads not
+  compete for the same key cache lock better. Unfortunately if we use a
+  partitioned key cache with N partitions for B-tree indexes we can't say
+  that the chances becomes N times less. The fact is that any index lookup
+  operation requires reading from the root page that, for any index, is always
+  ascribed to the same partition. To resolve this problem we should have
+  employed more sophisticated mechanisms of working with root pages.
+
+  Currently the number of partitions in a partitioned key cache is limited 
+  by 64. We could increase this limit. Simultaneously we would have to increase
+  accordingly the size of the bitmap dirty_part_map from the MYISAM_SHARE
+  structure.
+     
+******************************************************************************/
+
+/* Control block for a partitioned key cache */
+
+typedef struct st_partitioned_key_cache_cb
+{
+  my_bool key_cache_inited;     /*<=> control block is allocated            */ 
+  SIMPLE_KEY_CACHE_CB **partition_array; /* the key cache partitions        */  
+  size_t key_cache_mem_size;    /* specified size of the cache memory       */
+  uint key_cache_block_size;    /* size of the page buffer of a cache block */ 
+  uint partitions;              /* number of partitions in the key cache    */
+} PARTITIONED_KEY_CACHE_CB;
+
+static
+void end_partitioned_key_cache(PARTITIONED_KEY_CACHE_CB *keycache,
+                               my_bool cleanup);
+
+static int
+reset_partitioned_key_cache_counters(const char *name,
+                                     PARTITIONED_KEY_CACHE_CB *keycache);
+
+/*
+  Determine the partition to which the index block to read is ascribed
+
+  SYNOPSIS
+    get_key_cache_partition()
+    keycache            pointer to the control block of a partitioned key cache
+    file                handler for the file for the block of data to be read
+    filepos             position of the block of data in the file
+
+  DESCRIPTION
+    The function determines the number of the partition in whose buffer the 
+    block from 'file' at the position filepos has to be placed for reading.
+    The function returns the control block of the simple key cache for this
+    partition to the caller.
+
+  RETURN VALUE
+    The pointer to the control block of the partition to which the specified
+    file block is ascribed.
+*/
+
+static 
+SIMPLE_KEY_CACHE_CB *
+get_key_cache_partition(PARTITIONED_KEY_CACHE_CB *keycache, 
+                        File file, my_off_t filepos)
+{
+  uint i= KEYCACHE_BASE_EXPR(file, filepos) % keycache->partitions;
+  return keycache->partition_array[i];
+}
+
+
+/*
+  Determine the partition to which the index block to write is ascribed
+
+  SYNOPSIS
+    get_key_cache_partition()
+    keycache            pointer to the control block of a partitioned key cache
+    file                handler for the file for the block of data to be read
+    filepos             position of the block of data in the file
+    dirty_part_map      pointer to the bitmap of dirty partitions for the file
+
+  DESCRIPTION
+    The function determines the number of the partition in whose buffer the 
+    block from 'file' at the position filepos has to be placed for writing and
+    marks the partition as dirty in the dirty_part_map bitmap.
+    The function returns the control block of the simple key cache for this
+    partition to the caller.
+
+  RETURN VALUE
+    The pointer to the control block of the partition to which the specified
+    file block is ascribed.
+*/
+
+static SIMPLE_KEY_CACHE_CB 
+*get_key_cache_partition_for_write(PARTITIONED_KEY_CACHE_CB *keycache, 
+                                   File file, my_off_t filepos,
+                                   ulonglong* dirty_part_map)
+{
+  uint i= KEYCACHE_BASE_EXPR( file, filepos) % keycache->partitions;
+  *dirty_part_map|= 1<<i; 
+  return keycache->partition_array[i];
+}
+
+
+/*
+  Initialize a partitioned key cache
+
+  SYNOPSIS
+    init_partitioned_key_cache()
+    keycache            pointer to the control block of a partitioned key cache
+    key_cache_block_size    size of blocks to keep cached data
+    use_mem             total memory to use for all key cache partitions 
+    division_limit      division limit (may be zero)
+    age_threshold       age threshold (may be zero)
+
+  DESCRIPTION
+    This function is the implementation of the init_key_cache interface function
+    that is employed by partitioned key caches.
+    The function builds and initializes an array of simple key caches, and then
+    initializes the control block structure of the type PARTITIONED_KEY_CACHE_CB
+    that is used for a partitioned key cache. The parameter keycache is
+    supposed to point to this structure. The number of partitions in the
+    partitioned key cache to be built must be passed through the field
+    'partitions' of this structure. The parameter key_cache_block_size specifies
+    the size of the  blocks in the the simple key caches to be built.
+    The parameters division_limit and  age_threshold determine the initial
+    values of those characteristics of the simple key caches that are used for
+    midpoint insertion strategy. The parameter use_mem specifies the total
+    amount of memory to be allocated for the key cache blocks in all simple key
+    caches and for all auxiliary structures.       
+
+  RETURN VALUE
+    total number of blocks in key cache partitions, if successful,
+    <= 0 - otherwise.
+
+  NOTES
+    If keycache->key_cache_inited != 0 then we assume that the memory for
+    the array of partitions has been already allocated.
+
+    It's assumed that no two threads call this function simultaneously
+    referring to the same key cache handle.
+*/
+
+static
+int init_partitioned_key_cache(PARTITIONED_KEY_CACHE_CB *keycache,
+                               uint key_cache_block_size,
+                               size_t use_mem, uint division_limit,
+                               uint age_threshold)
+{
+  int i;
+  size_t mem_per_cache;
+  size_t mem_decr;
+  int cnt;
+  SIMPLE_KEY_CACHE_CB *partition;
+  SIMPLE_KEY_CACHE_CB **partition_ptr;
+  uint partitions= keycache->partitions;
+  int blocks= 0;
+  DBUG_ENTER("partitioned_init_key_cache");
+
+  keycache->key_cache_block_size = key_cache_block_size;
+
+  if (keycache->key_cache_inited)
+    partition_ptr= keycache->partition_array;
+  else
+  {
+    if(!(partition_ptr=
+       (SIMPLE_KEY_CACHE_CB **) my_malloc(sizeof(SIMPLE_KEY_CACHE_CB *) *
+                                          partitions, MYF(MY_WME))))
+      DBUG_RETURN(-1);
+    bzero(partition_ptr, sizeof(SIMPLE_KEY_CACHE_CB *) * partitions);
+    keycache->partition_array= partition_ptr;
+  }
+
+  mem_decr= mem_per_cache / 5;
+  mem_per_cache = use_mem / partitions;
+
+  for (i= 0; i < (int) partitions; i++)
+  {
+    my_bool key_cache_inited= keycache->key_cache_inited;
+    if (key_cache_inited)
+      partition= *partition_ptr;
+    else
+    {
+      if (!(partition=
+              (SIMPLE_KEY_CACHE_CB *)  my_malloc(sizeof(SIMPLE_KEY_CACHE_CB),
+						 MYF(MY_WME))))
+        continue;
+      partition->key_cache_inited= 0;
+    }
+
+    cnt= init_simple_key_cache(partition, key_cache_block_size, mem_per_cache, 
+			       division_limit, age_threshold);
+    if (cnt <= 0)
+    {
+      end_simple_key_cache(partition, 1);
+      if (!key_cache_inited)
+      {
+        my_free(partition,  MYF(0));
+        partition= 0;
+      }
+      if (i == 0 && cnt < 0 || i > 0)
+      {
+        /* 
+          Here we have two cases: 
+            1. i == 0 and cnt < 0
+            cnt < 0 => mem_per_cache is not big enough to allocate minimal
+            number of key blocks in the key cache of the partition.
+            Decrease the the number of the partitions by 1 and start again.
+            2. i > 0 
+            There is not enough memory for one of the succeeding partitions.
+            Just skip this partition decreasing the number of partitions in
+            the key cache by one.
+          Do not change the value of mem_per_cache in both cases.
+	*/
+        if (key_cache_inited)
+	{
+          my_free(partition,  MYF(0));
+          partition= 0;
+          if(key_cache_inited) 
+            memmove(partition_ptr, partition_ptr+1, 
+                    sizeof(partition_ptr)*(partitions-i-1));
+	}
+        if (!--partitions)
+          break;
+      }
+      else
+      {
+        /*
+          We come here when i == 0 && cnt == 0.
+          cnt == 0 => the memory allocator fails to allocate a block of
+          memory of the size mem_per_cache. Decrease the value of
+          mem_per_cache  without changing the current number of partitions
+          and start again. Make sure that such a decrease may happen not
+          more than 5 times in total.
+	*/
+        if (use_mem <= mem_decr)
+          break;
+        use_mem-= mem_decr;
+      }
+      i--;
+      mem_per_cache= use_mem/partitions;
+      continue;
+    }
+    else
+    {
+      blocks+= cnt;
+      *partition_ptr++= partition;
+    }
+  } 
+
+  keycache->partitions= partitions= partition_ptr-keycache->partition_array;
+  keycache->key_cache_mem_size= mem_per_cache * partitions;
+  for (i= 0; i < (int) partitions; i++)
+    keycache->partition_array[i]->hash_factor= partitions;
+  
+  keycache->key_cache_inited= 1;
+
+  if (!partitions)
+    blocks= -1;
+
+  DBUG_RETURN(blocks);
+} 
+
+
+/*
+  Resize a partitioned key cache
+
+  SYNOPSIS
+    resize_partitioned_key_cache()
+    keycache            pointer to the control block of a partitioned key cache
+    key_cache_block_size    size of blocks to keep cached data
+    use_mem             total memory to use for the new key cache
+    division_limit      new division limit (if not zero)
+    age_threshold       new age threshold (if not zero)
+
+  DESCRIPTION
+    This function is the implementation of the resize_key_cache interface
+    function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for the
+    partitioned key cache to be resized. 
+    The parameter key_cache_block_size specifies the new size of the blocks in
+    the simple key caches that comprise the partitioned key cache.
+    The parameters division_limit and age_threshold determine the new initial
+    values of those characteristics of the simple key cache that are used for
+    midpoint insertion strategy. The parameter use-mem specifies the total
+    amount of  memory to be allocated for the key cache blocks in all new
+    simple key caches and for all auxiliary structures.
+
+  RETURN VALUE
+    number of blocks in the key cache, if successful,
+    0 - otherwise.
+
+  NOTES.
+    The function first calls prepare_resize_simple_key_cache for each simple
+    key cache effectively flushing all dirty pages from it and destroying
+    the key cache. Then init_partitioned_key_cache is called. This call builds
+    a new array of simple key caches containing the same number of elements
+    as the old one. After this the function calls the function
+    finish_resize_simple_key_cache for each simple key cache from this array. 
+
+    This implementation doesn't block the calls and executions of other
+    functions from the key cache interface. However it assumes that the
+    calls of resize_partitioned_key_cache itself are serialized.
+*/
+
+static
+int resize_partitioned_key_cache(PARTITIONED_KEY_CACHE_CB *keycache, 
+                                 uint key_cache_block_size,
+		                 size_t use_mem, uint division_limit,
+		                 uint age_threshold)
+{
+  uint i;
+  uint partitions= keycache->partitions;
+  my_bool cleanup= use_mem == 0;
+  int blocks= -1;
+  int err= 0;
+  DBUG_ENTER("partitioned_resize_key_cache");
+  if (cleanup)
+  {
+    end_partitioned_key_cache(keycache, 0);
+    DBUG_RETURN(-1);
+  }
+  for (i= 0; i < partitions; i++)
+  {
+    err|= prepare_resize_simple_key_cache(keycache->partition_array[i], 0, 1);
+  }
+  if (!err) 
+    blocks= init_partitioned_key_cache(keycache, key_cache_block_size,
+                                       use_mem, division_limit, age_threshold);
+  if (blocks > 0)
+  {
+    for (i= 0; i < partitions; i++)
+    {
+      finish_resize_simple_key_cache(keycache->partition_array[i], 0, 1);
+    }
+  }
+  DBUG_RETURN(blocks);
+}
+
+
+/*
+  Change key cache parameters of a partitioned key cache
+
+  SYNOPSIS
+    partitioned_change_key_cache_param()
+    keycache            pointer to the control block of a partitioned key cache
+    division_limit      new division limit (if not zero)
+    age_threshold       new age threshold (if not zero)
+
+  DESCRIPTION
+    This function is the implementation of the change_key_cache_param interface
+    function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for the simple
+    key cache where new values of the division limit and the age threshold used
+    for midpoint insertion strategy are to be set.  The parameters
+    division_limit and age_threshold provide these new values.
+
+  RETURN VALUE
+    none
+
+  NOTES
+    The function just calls change_simple_key_cache_param for each element from
+    the array of simple caches that comprise the partitioned key cache. 
+*/
+
+static
+void change_partitioned_key_cache_param(PARTITIONED_KEY_CACHE_CB *keycache,
+                                        uint division_limit,
+                                        uint age_threshold)
+{
+  uint i;
+  uint partitions= keycache->partitions;
+  DBUG_ENTER("partitioned_change_key_cache_param");
+  for (i= 0; i < partitions; i++)
+  {
+    change_simple_key_cache_param(keycache->partition_array[i], division_limit,
+                                  age_threshold);
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Destroy a partitioned key cache 
+
+  SYNOPSIS
+    end_partitioned_key_cache()
+    keycache            pointer to the control block of a partitioned key cache
+    cleanup             <=> complete free (free also control block structures
+                            for all simple key caches)
+
+  DESCRIPTION
+    This function is the implementation of the end_key_cache interface
+    function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for the
+    partitioned key cache to be destroyed.
+    The function frees the memory allocated for the cache blocks and
+    auxiliary structures used by simple key caches that comprise the
+    partitioned key cache. If the value of the parameter cleanup is TRUE 
+    then even the memory used for control blocks of the simple key caches
+    and the array of pointers to them are freed.
+
+  RETURN VALUE
+    none
+*/
+
+static
+void end_partitioned_key_cache(PARTITIONED_KEY_CACHE_CB *keycache,
+                               my_bool cleanup)
+{
+  uint i;
+  uint partitions= keycache->partitions;
+  DBUG_ENTER("partitioned_end_key_cache");
+  DBUG_PRINT("enter", ("key_cache: 0x%lx", (long) keycache));
+
+  for (i= 0; i < partitions; i++)
+  {
+    end_simple_key_cache(keycache->partition_array[i], cleanup);
+  }
+  if (cleanup)
+  {
+    for (i= 0; i < partitions; i++)
+      my_free((uchar*) keycache->partition_array[i], MYF(0));
+    my_free((uchar*) keycache->partition_array, MYF(0));
+    keycache->key_cache_inited= 0;
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Read a block of data from a partitioned key cache into a buffer
+
+  SYNOPSIS
+
+    partitioned_key_cache_read()
+    keycache            pointer to the control block of a partitioned key cache  
+    file                handler for the file for the block of data to be read
+    filepos             position of the block of data in the file
+    level               determines the weight of the data
+    buff                buffer to where the data must be placed
+    length              length of the buffer
+    block_length        length of the read data from a key cache block 
+    return_buffer       return pointer to the key cache buffer with the data
+
+  DESCRIPTION
+    This function is the implementation of the key_cache_read interface
+    function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for a
+    partitioned key cache.
+    In a general case the function reads a block of data from the key cache
+    into the buffer buff of the size specified by the parameter length. The
+    beginning of the  block of data to be read is  specified by the parameters
+    file and filepos. The length of the read data is the same as the length
+    of the buffer. The data is read into the buffer in key_cache_block_size
+    increments. To read each portion the function first finds out in what
+    partition of the key cache this portion(page) is to be saved, and calls
+    simple_key_cache_read with the pointer to the corresponding simple key as
+    its first parameter. 
+    If the parameter return_buffer is not ignored and its value is TRUE, and 
+    the data to be read of the specified size block_length can be read from one
+    key cache buffer, then the function returns a pointer to the data in the
+    key cache buffer.
+    The function takes into account parameters block_length and return buffer
+    only in a single-threaded environment.
+    The parameter 'level' is used only by the midpoint insertion strategy 
+    when the data or its portion cannot be found in the key cache. 
+   
+  RETURN VALUE
+    Returns address from where the data is placed if successful, 0 - otherwise.
+*/
+
+static
+uchar *partitioned_key_cache_read(PARTITIONED_KEY_CACHE_CB *keycache,
+                                  File file, my_off_t filepos, int level,
+                                  uchar *buff, uint length,
+                                  uint block_length __attribute__((unused)),
+                                  int return_buffer __attribute__((unused)))
+{
+  uint r_length;
+  uint offset= (uint) (filepos % keycache->key_cache_block_size);
+  uchar *start= buff;
+  DBUG_ENTER("partitioned_key_cache_read");
+  DBUG_PRINT("enter", ("fd: %u  pos: %lu  length: %u",
+               (uint) file, (ulong) filepos, length));
+
+#ifndef THREAD
+  if (block_length > keycache->key_cache_block_size || offset)
+    return_buffer=0;
+#endif
+
+  /* Read data in key_cache_block_size increments */
+  do
+  {
+    SIMPLE_KEY_CACHE_CB *partition= get_key_cache_partition(keycache, 
+                                                            file, filepos);
+    uchar *ret_buff= 0;
+    r_length= length;
+    set_if_smaller(r_length, keycache->key_cache_block_size - offset);
+    ret_buff= simple_key_cache_read((void *) partition, 
+                                    file, filepos, level,
+                                    buff, r_length,
+                                    block_length, return_buffer);
+    if (ret_buff == 0) 
+      DBUG_RETURN(0);
+#ifndef THREAD
+    /* This is only true if we were able to read everything in one block */
+    if (return_buffer)
+      DBUG_RETURN(ret_buff);
+#endif
+    filepos+= r_length;
+    buff+= r_length;
+    offset= 0;
+  } while ((length-= r_length));
+  
+  DBUG_RETURN(start);
+}
+
+
+/*
+  Insert a block of file data from a buffer into a partitioned key cache
+
+  SYNOPSIS
+    partitioned_key_cache_insert()
+    keycache            pointer to the control block of a partitioned key cache 
+    file                handler for the file to insert data from
+    filepos             position of the block of data in the file to insert
+    level               determines the weight of the data
+    buff                buffer to read data from
+    length              length of the data in the buffer
+
+  DESCRIPTION
+    This function is the implementation of the key_cache_insert interface
+    function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for a
+    partitioned key cache.
+    The function writes a block of file data from a buffer into the key cache.
+    The buffer is specified with the parameters buff and length - the pointer
+    to the beginning of the buffer and its size respectively. It's assumed
+    that the buffer contains the data from 'file' allocated from the position
+    filepos. The data is copied from the buffer in key_cache_block_size 
+    increments. For every portion of data the function finds out in what simple
+    key cache from the array of partitions the data must be stored, and after
+    this calls simple_key_cache_insert to copy the data into a key buffer of
+    this simple key cache.
+    The parameter level is used to set one characteristic for the key buffers
+    loaded with the data from buff. The characteristic is used only by the
+    midpoint insertion strategy. 
+   
+  RETURN VALUE
+    0 if a success, 1 - otherwise.
+
+  NOTES
+    The function is used by MyISAM to move all blocks from a index file to 
+    the key cache. It can be performed in parallel with reading the file data
+    from the key buffers by other threads.
+*/
+
+static
+int partitioned_key_cache_insert(PARTITIONED_KEY_CACHE_CB *keycache,
+                                 File file, my_off_t filepos, int level,
+                                 uchar *buff, uint length)
+{
+  uint w_length;
+  uint offset= (uint) (filepos % keycache->key_cache_block_size);
+  DBUG_ENTER("partitioned_key_cache_insert");
+  DBUG_PRINT("enter", ("fd: %u  pos: %lu  length: %u",
+               (uint) file,(ulong) filepos, length));
+
+
+  /* Write data in key_cache_block_size increments */
+  do
+  {
+    SIMPLE_KEY_CACHE_CB *partition= get_key_cache_partition(keycache, 
+                                                            file, filepos);
+    w_length= length;
+    set_if_smaller(w_length, keycache->key_cache_block_size - offset);
+    if (simple_key_cache_insert((void *) partition,
+                                file, filepos, level,
+                                buff, w_length)) 
+      DBUG_RETURN(1);
+
+    filepos+= w_length;
+    buff+= w_length;
+    offset = 0;
+  } while ((length-= w_length));
+  
+  DBUG_RETURN(0);
+}
+
+
+/*
+  Write data from a buffer into a partitioned key cache
+
+  SYNOPSIS
+
+    partitioned_key_cache_write()
+    keycache            pointer to the control block of a partitioned key cache
+    file                handler for the file to write data to
+    filepos             position in the file to write data to
+    level               determines the weight of the data
+    buff                buffer with the data
+    length              length of the buffer
+    dont_write          if is 0 then all dirty pages involved in writing
+                        should have been flushed from key cache
+    file_extra          maps of key cache partitions containing 
+                        dirty pages from file 
+
+  DESCRIPTION
+    This function is the implementation of the key_cache_write interface
+    function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for a
+    partitioned key cache.
+    In a general case the function copies data from a buffer into the key
+    cache. The buffer is specified with the parameters buff and length -
+    the pointer to the beginning of the buffer and its size respectively.
+    It's assumed the buffer contains the data to be written into 'file'
+    starting from the position filepos. The data is copied from the buffer
+    in key_cache_block_size increments. For every portion of data the
+    function finds out in what simple key cache from the array of partitions
+    the data must be stored, and after this calls simple_key_cache_write to
+    copy the data into a key buffer of this simple key cache.
+    If the value of the parameter dont_write is FALSE then the function
+    also writes the data into file.
+    The parameter level is used to set one characteristic for the key buffers
+    filled with the data from buff. The characteristic is employed only by
+    the midpoint insertion strategy.
+    The parameter file_expra provides a pointer to the shared bitmap of
+    the partitions that may contains dirty pages for the file. This bitmap
+    is used to optimize the function flush_partitioned_key_cache_blocks. 
+
+  RETURN VALUE
+    0 if a success, 1 - otherwise.
+
+  NOTES
+    This implementation exploits the fact that the function is called only
+    when a thread has got an exclusive lock for the key file.
+*/
+
+static
+int partitioned_key_cache_write(PARTITIONED_KEY_CACHE_CB *keycache,
+                                File file, void *file_extra,
+                                my_off_t filepos, int level,
+                                uchar *buff, uint length,
+                                uint block_length  __attribute__((unused)),
+                                int dont_write)
+{
+  uint w_length;
+  ulonglong *part_map= (ulonglong *) file_extra;
+  uint offset= (uint) (filepos % keycache->key_cache_block_size);
+  DBUG_ENTER("partitioned_key_cache_write");
+  DBUG_PRINT("enter",
+             ("fd: %u  pos: %lu  length: %u  block_length: %u"
+              "  key_block_length: %u",
+              (uint) file, (ulong) filepos, length, block_length,
+              keycache ? keycache->key_cache_block_size : 0));
+
+
+  /* Write data in key_cache_block_size increments */
+  do
+  {
+    SIMPLE_KEY_CACHE_CB *partition= get_key_cache_partition_for_write(keycache, 
+                                                                      file,
+                                                                      filepos,
+                                                                      part_map);
+    w_length = length;
+    set_if_smaller(w_length, keycache->key_cache_block_size - offset );
+    if (simple_key_cache_write(partition,
+                               file, 0, filepos, level,
+                               buff, w_length, block_length,
+                               dont_write))
+      DBUG_RETURN(1);
+
+    filepos+= w_length;
+    buff+= w_length;
+    offset= 0;
+  } while ((length-= w_length));
+
+  DBUG_RETURN(0);
+}
+
+
+/*
+  Flush all blocks for a file from key buffers of a partitioned key cache 
+
+  SYNOPSIS
+
+    flush_partitioned_key_cache_blocks()
+    keycache            pointer to the control block of a partitioned key cache
+    file                handler for the file to flush to
+    file_extra          maps of key cache partitions containing 
+                        dirty pages from file (not used)         
+    flush_type          type of the flush operation
+
+  DESCRIPTION
+    This function is the implementation of the flush_key_blocks interface
+    function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for a
+    partitioned key cache.
+    In a general case the function flushes the data from all dirty key
+    buffers related to the file 'file' into this file. The function does
+    exactly this if the value of the parameter type is FLUSH_KEEP. If the
+    value of this parameter is FLUSH_RELEASE, the function additionally 
+    releases the key buffers containing data from 'file' for new usage.
+    If the value of the parameter type is FLUSH_IGNORE_CHANGED the function
+    just releases the key buffers containing data from 'file'.
+    The function performs the operation by calling the function 
+    flush_simple_key_cache_blocks for the elements of the array of the
+    simple key caches that comprise the partitioned key_cache. If the value
+    of the parameter type is FLUSH_KEEP s_flush_key_blocks is called only
+    for the partitions with possibly dirty pages marked in the bitmap
+    pointed to by the parameter file_extra.    
+      
+  RETURN
+    0   ok
+    1  error
+
+  NOTES
+    This implementation exploits the fact that the function is called only
+    when a thread has got an exclusive lock for the key file.
+*/
+
+static
+int flush_partitioned_key_cache_blocks(PARTITIONED_KEY_CACHE_CB *keycache,
+                                       File file, void *file_extra,
+                                       enum flush_type type)
+{
+  uint i;
+  uint partitions= keycache->partitions;
+  int err= 0;
+  ulonglong *dirty_part_map= (ulonglong *) file_extra;
+  DBUG_ENTER("partitioned_flush_key_blocks");
+  DBUG_PRINT("enter", ("keycache: 0x%lx", (long) keycache));
+
+  for (i= 0; i < partitions; i++)
+  {
+    SIMPLE_KEY_CACHE_CB *partition= keycache->partition_array[i];
+    if ((type == FLUSH_KEEP || type == FLUSH_FORCE_WRITE) &&
+        !((*dirty_part_map) & ((ulonglong) 1 << i)))
+      continue;
+    err|= test(flush_simple_key_cache_blocks(partition, file, 0, type));
+  }
+  *dirty_part_map= 0;
+
+  DBUG_RETURN(err);
+}
+
+
+/*
+  Reset the counters of a partitioned key cache
+
+  SYNOPSIS
+    reset_partitioned_key_cache_counters()
+    name                the name of a key cache
+    keycache            pointer to the control block of a partitioned key cache
+
+  DESCRIPTION
+    This function is the implementation of the reset_key_cache_counters
+    interface function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for a partitioned
+    key cache.
+    This function resets the values of the statistical counters of the simple
+    key caches comprising partitioned key cache to 0. It does it by calling 
+    reset_simple_key_cache_counters for each key  cache partition. 
+    The parameter name is currently not used.
+
+  RETURN
+    0 on success (always because it can't fail)
+*/
+
+static int
+reset_partitioned_key_cache_counters(const char *name __attribute__((unused)),
+                                     PARTITIONED_KEY_CACHE_CB *keycache)
+{
+  uint i;
+  uint partitions= keycache->partitions;
+  DBUG_ENTER("partitioned_reset_key_cache_counters");
+
+  for (i = 0; i < partitions; i++)
+  {
+    reset_simple_key_cache_counters(name,  keycache->partition_array[i]);
+  }
+  DBUG_RETURN(0);
+}
+
+
+/*
+  Get statistics for a partition key cache 
+
+  SYNOPSIS
+    get_partitioned_key_cache_statistics()
+    keycache            pointer to the control block of a partitioned key cache
+    partition_no        partition number to get statistics for
+    key_cache_stats OUT pointer to the structure for the returned statistics
+
+  DESCRIPTION
+    This function is the implementation of the get_key_cache_statistics
+    interface function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for
+    a partitioned key cache.
+    If the value of the parameter partition_no is equal to 0 then aggregated
+    statistics for all partitions is returned in the fields of the
+    structure key_cache_stat of the type KEY_CACHE_STATISTICS . Otherwise
+    the function returns data for the partition number partition_no of the
+    key cache in the structure key_cache_stat. (Here partitions are numbered
+    starting from 1.)
+
+  RETURN
+    none
+*/
+
+static
+void
+get_partitioned_key_cache_statistics(PARTITIONED_KEY_CACHE_CB *keycache,
+                                     uint partition_no, 
+                                     KEY_CACHE_STATISTICS *keycache_stats)
+{
+  uint i;
+  SIMPLE_KEY_CACHE_CB *partition;
+  uint partitions= keycache->partitions;
+  DBUG_ENTER("get_partitioned_key_cache_statistics");
+
+  if (partition_no != 0)
+  { 
+    partition= keycache->partition_array[partition_no-1];
+    get_simple_key_cache_statistics((void *) partition, 0, keycache_stats);
+    DBUG_VOID_RETURN;
+  }
+  bzero(keycache_stats, sizeof(KEY_CACHE_STATISTICS));  
+  keycache_stats->mem_size= (longlong) keycache->key_cache_mem_size;
+  keycache_stats->block_size= (longlong) keycache->key_cache_block_size;
+  for (i = 0; i < partitions; i++)
+  {
+    partition= keycache->partition_array[i];
+    keycache_stats->blocks_used+= partition->blocks_used;
+    keycache_stats->blocks_unused+= partition->blocks_unused;
+    keycache_stats->blocks_changed+= partition->global_blocks_changed;
+    keycache_stats->read_requests+= partition->global_cache_r_requests;
+    keycache_stats->reads+= partition->global_cache_read;
+    keycache_stats->write_requests+= partition->global_cache_w_requests;
+    keycache_stats->writes+= partition->global_cache_write;
+  }
+  DBUG_VOID_RETURN;  
+}
+
+/*
+  Get the value of a statistical variable for a partitioned key cache
+
+  SYNOPSIS
+    get_partitioned_key_cache_stat_value()
+    keycache            pointer to the control block of a partitioned key cache
+    var_no              the ordered number of a statistical variable 
+
+  DESCRIPTION
+    This function is the implementation of the get_key_cache_stat_value
+    interface function that is employed by partitioned key caches.
+    The function takes the parameter keycache as a pointer to the
+    control block structure of the type PARTITIONED_KEY_CACHE_CB for a
+    partitioned key cache.
+    This function returns the value of the statistical variable var_no
+    for this key cache. The variables are numbered starting from 0 to 6.
+    The returned value is calculated as the sum of the values of the
+    statistical variable with number var_no for all simple key caches that
+    comprise the partitioned key cache.
+
+  RETURN
+    The value of the specified statistical variable 
+*/
+
+static
+ulonglong
+get_partitioned_key_cache_stat_value(PARTITIONED_KEY_CACHE_CB *keycache,
+                                     uint var_no)
+{
+  uint i;
+  uint partitions= keycache->partitions;
+  size_t var_ofs= simple_key_cache_stat_var_offsets[var_no];
+  ulonglong res= 0;
+  DBUG_ENTER("get_partitioned_key_cache_stat_value");
+
+  if (var_no < NUM_LONG_KEY_CACHE_STAT_VARIABLES)
+  {
+    for (i = 0; i < partitions; i++)
+    {
+      SIMPLE_KEY_CACHE_CB *partition= keycache->partition_array[i];
+      res+= (ulonglong) (*(long *) ((char *) partition + var_ofs));
+    }
+  }
+  else
+  {
+    for (i = 0; i < partitions; i++)
+    {
+      SIMPLE_KEY_CACHE_CB *partition= keycache->partition_array[i];
+      res+= *(ulonglong *) ((char *) partition + var_ofs);
+    }
+  }
+  DBUG_RETURN(res);
+}
+
+
+/* 
+  The array of pointers to the key cache interface functions used by 
+  partitioned key caches. Any partitioned key cache object caches exploits
+  this array.
+ 
+  The current implementation of these functions does not allow to call
+  them from the MySQL server code directly. The key cache interface
+  wrappers must be used for this purpose. 
+*/
+
+static KEY_CACHE_FUNCS partitioned_key_cache_funcs =
+{
+  (INIT_KEY_CACHE) init_partitioned_key_cache,
+  (RESIZE_KEY_CACHE) resize_partitioned_key_cache,
+  (CHANGE_KEY_CACHE_PARAM) change_partitioned_key_cache_param,      
+  (KEY_CACHE_READ) partitioned_key_cache_read,
+  (KEY_CACHE_INSERT) partitioned_key_cache_insert,
+  (KEY_CACHE_WRITE) partitioned_key_cache_write,
+  (FLUSH_KEY_BLOCKS) flush_partitioned_key_cache_blocks, 
+  (RESET_KEY_CACHE_COUNTERS) reset_partitioned_key_cache_counters, 
+  (END_KEY_CACHE) end_partitioned_key_cache, 
+  (GET_KEY_CACHE_STATISTICS) get_partitioned_key_cache_statistics,
+  (GET_KEY_CACHE_STAT_VALUE) get_partitioned_key_cache_stat_value
+};
+
+
+/****************************************************************************** 
+  Key Cache Interface Module
+
+  The module contains wrappers for all key cache interface functions. 
+  
+  Currently there are key caches of two types: simple key caches and
+  partitioned key caches. Each type (class) has its own implementation of the
+  basic key cache operations used the MyISAM storage engine. The pointers
+  to the implementation functions are stored in two static structures of the
+  type KEY_CACHE_FUNC: simple_key_cache_funcs - for simple key caches, and
+  partitioned_key_cache_funcs - for partitioned key caches. When a key cache
+  object is created the constructor procedure init_key_cache places a pointer
+  to the corresponding table into one of its fields. The procedure also
+  initializes a control block for the key cache oject and saves the pointer
+  to this block in another field of the key cache object.
+  When a key cache wrapper function is invoked for a key cache object to
+  perform a basic key cache operation it looks into the interface table
+  associated with the key cache oject and calls the corresponding
+  implementation of the operation. It passes the saved key cache control
+  block to this implementation. If, for some reasons, the control block
+  has not been fully initialized yet, the wrapper function either does not
+  do anything or, in the case when it perform a read/write operation, the
+  function do it directly through the system i/o functions.
+
+  As we can see the model with which the key cache interface is supported
+  as quite conventional for interfaces in general.
+          
+******************************************************************************/
+
+
+/*
+  Initialize a key cache
+
+  SYNOPSIS
+    init_key_cache()
+    keycache           pointer to the key cache to be initialized
+    key_cache_block_size    size of blocks to keep cached data
+    use_mem             total memory to use for cache buffers/structures 
+    division_limit      division limit (may be zero)
+    age_threshold       age threshold (may be zero)
+    partitions          number of partitions in the key cache
+
+  DESCRIPTION
+    The function creates a control block structure for a key cache and
+    places the pointer to this block in the structure keycache. 
+    If the value of the parameter 'partitions' is 0 then a simple key cache
+    is created. Otherwise a partitioned key cache with the specified number
+    of partitions is created.  
+    The parameter key_cache_block_size specifies the size of the blocks in
+    the key cache to be created. The parameters division_limit and
+    age_threshold determine the initial values of those characteristics of
+    the key cache that are used for midpoint insertion strategy. The parameter
+    use_mem  specifies the total amount of memory to be allocated for the
+    key cache buffers and for all auxiliary structures.       
+
+  RETURN VALUE
+    total number of blocks in key cache partitions, if successful,
+    <= 0 - otherwise.
+
+  NOTES
+    if keycache->key_cache_inited != 0 we assume that the memory
+    for the control block of the key cache has been already allocated.
+
+    It's assumed that no two threads call this function simultaneously
+    referring to the same key cache handle.
+*/
+
+int init_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
+		   size_t use_mem, uint division_limit,
+		   uint age_threshold, uint partitions)
+{
+  void *keycache_cb;
+  int blocks;
+  if (keycache->key_cache_inited)
+    keycache_cb= keycache->keycache_cb;
+  else
+  {
+    if (partitions == 0)
+    {
+      if (!(keycache_cb= (void *)  my_malloc(sizeof(SIMPLE_KEY_CACHE_CB),
+                                             MYF(0)))) 
+        return 0;
+      ((SIMPLE_KEY_CACHE_CB *) keycache_cb)->key_cache_inited= 0;
+      keycache->key_cache_type= SIMPLE_KEY_CACHE;
+      keycache->interface_funcs= &simple_key_cache_funcs;
+    }
+    else
+    {
+      if (!(keycache_cb= (void *)  my_malloc(sizeof(PARTITIONED_KEY_CACHE_CB),
+                                             MYF(0)))) 
+        return 0;
+      ((PARTITIONED_KEY_CACHE_CB *) keycache_cb)->key_cache_inited= 0;
+      keycache->key_cache_type= PARTITIONED_KEY_CACHE;
+      keycache->interface_funcs= &partitioned_key_cache_funcs;
+    }
+    keycache->keycache_cb= keycache_cb;
+    keycache->key_cache_inited= 1;
+  }
+
+  if (partitions != 0)
+  {
+    ((PARTITIONED_KEY_CACHE_CB *) keycache_cb)->partitions= partitions;
+  }
+  keycache->can_be_used= 0;
+  blocks= keycache->interface_funcs->init(keycache_cb, key_cache_block_size,
+                                          use_mem, division_limit,
+                                          age_threshold);
+  keycache->partitions= partitions ? 
+                        ((PARTITIONED_KEY_CACHE_CB *) keycache_cb)->partitions :
+                        0;
+  DBUG_ASSERT(partitions <= MAX_KEY_CACHE_PARTITIONS);
+  if (blocks > 0)
+    keycache->can_be_used= 1;
+  return blocks;
+}
+
+
+/*
+  Resize a key cache
+
+  SYNOPSIS
+    resize_key_cache()
+    keycache            pointer to the key cache to be resized
+    key_cache_block_size    size of blocks to keep cached data
+    use_mem             total memory to use for the new key cache
+    division_limit      new division limit (if not zero)
+    age_threshold       new age threshold (if not zero)
+
+  DESCRIPTION
+    The function operates over the key cache key cache.
+    The parameter key_cache_block_size specifies the new size of the block
+    buffers in the key cache. The parameters division_limit and age_threshold
+    determine the new initial values of those characteristics of the key cache
+    that are used for midpoint insertion strategy. The parameter use_mem
+    specifies the total amount of  memory to be allocated for the key cache
+    buffers and for all auxiliary structures.
+
+  RETURN VALUE
+    number of blocks in the key cache, if successful,
+    0 - otherwise.
+
+  NOTES
+    The function does not block the calls and executions of other functions
+    from the key cache interface. However it assumes that the calls of 
+    resize_key_cache itself are serialized.
+
+    Currently the function is called when the values of the variables
+    key_buffer_size and/or key_cache_block_size are being reset for
+    the key cache keycache.
+*/
+
+int resize_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
+		     size_t use_mem, uint division_limit, uint age_threshold)
+{
+  int blocks= -1;
+  if (keycache->key_cache_inited)
+  {
+    if ((uint) keycache->param_partitions != keycache->partitions && use_mem)
+      blocks= repartition_key_cache(keycache,
+                                    key_cache_block_size, use_mem,
+                                    division_limit, age_threshold, 
+                                    (uint) keycache->param_partitions);
+    else
+    {
+      blocks= keycache->interface_funcs->resize(keycache->keycache_cb,
+                                                key_cache_block_size,
+                                                use_mem, division_limit,
+                                                age_threshold);
+
+      if (keycache->partitions)
+        keycache->partitions=
+          ((PARTITIONED_KEY_CACHE_CB *)(keycache->keycache_cb))->partitions;
+    }
+
+    keycache->can_be_used= (blocks >= 0);
+  } 
+  return blocks;
+}
+
+
+/*
+  Change key cache parameters of a key cache
+
+  SYNOPSIS
+    change_key_cache_param()
+    keycache            pointer to the key cache to change parameters for
+    division_limit      new division limit (if not zero)
+    age_threshold       new age threshold (if not zero)
+
+  DESCRIPTION
+    The function sets new values of the division limit and the age threshold 
+    used when the key cache keycach employs midpoint insertion strategy.
+    The parameters division_limit and age_threshold provide these new values.
+
+  RETURN VALUE
+    none
+
+  NOTES
+    Currently the function is called when the values of the variables
+    key_cache_division_limit and/or key_cache_age_threshold are being reset
+    for the key cache keycache.
+*/
+
+void change_key_cache_param(KEY_CACHE *keycache, uint division_limit,
+			    uint age_threshold)
+{
+  if (keycache->key_cache_inited)
+  {
+    
+    keycache->interface_funcs->change_param(keycache->keycache_cb,
+                                            division_limit,
+                                            age_threshold);
+  }
+}
+
+
+/*
+  Destroy a key cache 
+
+  SYNOPSIS
+    end_key_cache()
+    keycache            pointer to the key cache to be destroyed
+    cleanup             <=> complete free 
+
+  DESCRIPTION
+    The function frees the memory allocated for the cache blocks and
+    auxiliary structures used by the key cache keycache. If the value
+    of the parameter cleanup is TRUE then all resources used by the key
+    cache are to be freed.
+
+  RETURN VALUE
+    none
+*/
+
+void end_key_cache(KEY_CACHE *keycache, my_bool cleanup)
+{
+  if (keycache->key_cache_inited)
+  {
+    keycache->interface_funcs->end(keycache->keycache_cb, cleanup);
+    if (cleanup)
+    {
+      if (keycache->keycache_cb)
+      {
+        my_free((uchar *) keycache->keycache_cb, MYF(0));
+        keycache->keycache_cb= 0;
+      }
+      keycache->key_cache_inited= 0;
+    }
+    keycache->can_be_used= 0;
+  }
+}
+
+
+/*
+  Read a block of data from a key cache into a buffer
+
+  SYNOPSIS
+
+    key_cache_read()
+    keycache            pointer to the key cache to read data from  
+    file                handler for the file for the block of data to be read
+    filepos             position of the block of data in the file
+    level               determines the weight of the data
+    buff                buffer to where the data must be placed
+    length              length of the buffer
+    block_length        length of the data read from a key cache block 
+    return_buffer       return pointer to the key cache buffer with the data
+
+  DESCRIPTION
+    The function operates over buffers of the key cache keycache.
+    In a general case the function reads a block of data from the key cache
+    into the buffer buff of the size specified by the parameter length. The
+    beginning of the block of data to be read is specified by the parameters
+    file and filepos. The length of the read data is the same as the length
+    of the buffer.
+    If the parameter return_buffer is not ignored and its value is TRUE, and 
+    the data to be read of the specified size block_length can be read from one
+    key cache buffer, then the function returns a pointer to the data in the
+    key cache buffer.
+    The parameter 'level' is used only by the midpoint insertion strategy 
+    when the data or its portion cannot be found in the key cache.
+    The function reads data into the buffer directly from file if the control
+    block of the key cache has not been initialized yet. 
+   
+  RETURN VALUE
+    Returns address from where the data is placed if successful, 0 - otherwise.
+
+  NOTES.
+    Filepos must be a multiple of 'block_length', but it doesn't
+    have to be a multiple of key_cache_block_size;
+*/
+
+uchar *key_cache_read(KEY_CACHE *keycache, 
+                      File file, my_off_t filepos, int level,
+                      uchar *buff, uint length,
+		      uint block_length, int return_buffer)
+{
+  if (keycache->key_cache_inited && keycache->can_be_used)
+    return keycache->interface_funcs->read(keycache->keycache_cb,
+                                           file, filepos, level,
+                                           buff, length,
+                                           block_length, return_buffer);
+ 
+  /* We can't use mutex here as the key cache may not be initialized */
+  keycache->global_cache_r_requests++;
+  keycache->global_cache_read++;
+
+  if (my_pread(file, (uchar*) buff, length, filepos, MYF(MY_NABP)))
+    return (uchar *) 0;
+  
+  return buff;
+}
+
+
+/*
+  Insert a block of file data from a buffer into a key cache
+
+  SYNOPSIS
+    key_cache_insert()
+    keycache            pointer to the key cache to insert data into 
+    file                handler for the file to insert data from
+    filepos             position of the block of data in the file to insert
+    level               determines the weight of the data
+    buff                buffer to read data from
+    length              length of the data in the buffer
+
+  DESCRIPTION
+    The function operates over buffers of the key cache keycache.
+    The function writes a block of file data from a buffer into the key cache.
+    The buffer is specified with the parameters buff and length - the pointer
+    to the beginning of the buffer and its size respectively. It's assumed
+    that the buffer contains the data from 'file' allocated from the position
+    filepos.
+    The parameter level is used to set one characteristic for the key buffers
+    loaded with the data from buff. The characteristic is used only by the
+    midpoint insertion strategy. 
+   
+  RETURN VALUE
+    0 if a success, 1 - otherwise.
+
+  NOTES
+    The function is used by MyISAM to move all blocks from a index file to 
+    the key cache. 
+    It is assumed that it may be performed in parallel with reading the file
+    data from the key buffers by other threads.
+*/
+
+int key_cache_insert(KEY_CACHE *keycache,
+                     File file, my_off_t filepos, int level,
+                     uchar *buff, uint length)
+{
+  if (keycache->key_cache_inited && keycache->can_be_used)
+    return keycache->interface_funcs->insert(keycache->keycache_cb,
+                                             file, filepos, level,
+                                             buff, length);
+  return 0;
+}
+
+
+/*
+  Write data from a buffer into a key cache
+
+  SYNOPSIS
+
+    key_cache_write()
+    keycache            pointer to the key cache to write data to
+    file                handler for the file to write data to
+    filepos             position in the file to write data to
+    level               determines the weight of the data
+    buff                buffer with the data
+    length              length of the buffer
+    dont_write          if is 0 then all dirty pages involved in writing
+                        should have been flushed from key cache
+    file_extra          pointer to optional file attributes
+
+  DESCRIPTION
+    The function operates over buffers of the key cache keycache.
+    In a general case the function writes data from a buffer into the key
+    cache. The buffer is specified with the parameters buff and length -
+    the pointer to the beginning of the buffer and its size respectively.
+    It's assumed the buffer contains the data to be written into 'file'
+    starting from the position filepos. 
+    If the value of the parameter dont_write is FALSE then the function
+    also writes the data into file.
+    The parameter level is used to set one characteristic for the key buffers
+    filled with the data from buff. The characteristic is employed only by
+    the midpoint insertion strategy.
+    The parameter file_expra may point to additional file attributes used
+    for optimization or other purposes.
+    The function writes data from the buffer directly into file if the control
+    block of the key cache has not been initialized yet.      
+
+  RETURN VALUE
+    0 if a success, 1 - otherwise.
+
+  NOTES
+    This implementation may exploit the fact that the function is called only
+    when a thread has got an exclusive lock for the key file.
+*/
+
+int key_cache_write(KEY_CACHE *keycache,
+                    File file, void *file_extra,
+                    my_off_t filepos, int level,
+                    uchar *buff, uint length,
+		    uint block_length, int force_write)
+{
+  if (keycache->key_cache_inited && keycache->can_be_used)
+    return keycache->interface_funcs->write(keycache->keycache_cb,
+                                            file, file_extra,
+                                            filepos, level,
+                                            buff, length,
+                                            block_length, force_write);
+  
+  /* We can't use mutex here as the key cache may not be initialized */
+  keycache->global_cache_w_requests++;
+  keycache->global_cache_write++;
+  if (my_pwrite(file, buff, length, filepos, MYF(MY_NABP | MY_WAIT_IF_FULL)))
+    return 1;
+
+  return 0;
+}
+
+
+/*
+  Flush all blocks for a file from key buffers of a key cache 
+
+  SYNOPSIS
+
+    flush_key_blocks()
+    keycache            pointer to the key cache whose blocks are to be flushed
+    file                handler for the file to flush to
+    file_extra          maps of key cache (used for partitioned key caches)
+    flush_type          type of the flush operation
+
+  DESCRIPTION
+    The function operates over buffers of the key cache keycache.
+    In a general case the function flushes the data from all dirty key
+    buffers related to the file 'file' into this file. The function does
+    exactly this if the value of the parameter type is FLUSH_KEEP. If the
+    value of this parameter is FLUSH_RELEASE, the function additionally 
+    releases the key buffers containing data from 'file' for new usage.
+    If the value of the parameter type is FLUSH_IGNORE_CHANGED the function
+    just releases the key buffers containing data from 'file'.
+    If the value of the parameter type is FLUSH_KEEP the function may use
+    the value of the parameter file_extra pointing to possibly dirty
+    partitions to optimize the operation for partitioned key caches.
+      
+  RETURN
+    0   ok
+    1  error
+
+  NOTES
+    Any implementation of the function may exploit the fact that the function
+    is called only when a thread has got an exclusive lock for the key file.
+*/
+
+int flush_key_blocks(KEY_CACHE *keycache,
+                     int file, void *file_extra,
+                     enum flush_type type)
+{
+  if (keycache->key_cache_inited)
+    return keycache->interface_funcs->flush(keycache->keycache_cb,
+                                            file, file_extra, type);
+  return 0;  
+}
+
+
+/*
+  Reset the counters of a key cache
+
+  SYNOPSIS
+    reset_key_cache_counters()
+    name          the name of a key cache (unused)
+    keycache      pointer to the key cache for which to reset counters
+
+  DESCRIPTION
+    This function resets the values of the statistical counters for the key
+    cache keycache.
+    The parameter name is currently not used.
+
+  RETURN
+    0 on success (always because it can't fail)
+
+  NOTES
+   This procedure is used by process_key_caches() to reset the counters of all
+   currently used key caches, both the default one and the named ones.
+*/
+
+int reset_key_cache_counters(const char *name __attribute__((unused)),
+                             KEY_CACHE *keycache)
+{
+  if (keycache->key_cache_inited)
+  {
+    
+    return keycache->interface_funcs->reset_counters(name,
+                                                     keycache->keycache_cb);
+  }
+  return 0;
+}
+
+
+/*
+  Get statistics for a key cache
+
+  SYNOPSIS
+    get_key_cache_statistics()
+    keycache            pointer to the key cache to get statistics for
+    partition_no        partition number to get statistics for
+    key_cache_stats OUT pointer to the structure for the returned statistics
+
+  DESCRIPTION
+    If the value of the parameter partition_no is equal to 0 then statistics
+    for the whole key cache keycache (aggregated statistics) is returned in the
+    fields of the structure key_cache_stat of the type KEY_CACHE_STATISTICS.
+    Otherwise the value of the parameter partition_no makes sense only for
+    a partitioned key cache. In this case the function returns statistics
+    for the partition with the specified number partition_no.   
+  
+  RETURN
+    none
+*/
+
+void get_key_cache_statistics(KEY_CACHE *keycache, uint partition_no, 
+                              KEY_CACHE_STATISTICS *key_cache_stats)
+{
+  if (keycache->key_cache_inited)
+  {    
+    keycache->interface_funcs->get_stats(keycache->keycache_cb,
+                                         partition_no, key_cache_stats);
+  }
+}
+
+
+/*
+  Get the value of a statistical variable for a key cache
+
+  SYNOPSIS
+    get_key_cache_stat_value()
+    keycache            pointer to the key cache to get statistics for
+    var_no              the ordered number of a statistical variable 
+
+  DESCRIPTION
+    This function returns the value of the statistical variable var_no for
+    the key cache keycache. The variables are numbered starting from 0 to 6.
+
+  RETURN
+    The value of the specified statistical variable.
+
+  NOTES 
+    Currently for any key cache the function can return values for the
+    following 7 statistical variables:
+  
+    Name             Number
+    
+    blocks_used        0
+    blocks_unused      1
+    blocks_changed     2
+    read_requests      3
+    reads              4
+    write_requests     5
+    writes             6
+*/
+
+ulonglong get_key_cache_stat_value(KEY_CACHE *keycache, uint var_no)
+{
+  if (keycache->key_cache_inited)
+  {    
+    return keycache->interface_funcs->get_stat_val(keycache->keycache_cb,
+                                                   var_no);
+  }
+  else
+    return 0;
+}
+  
+
+/*
+  Repartition a key cache
+
+  SYNOPSIS
+    repartition_key_cache()
+    keycache           pointer to the key cache to be repartitioned
+    key_cache_block_size    size of blocks to keep cached data
+    use_mem             total memory to use for the new key cache
+    division_limit      new division limit (if not zero)
+    age_threshold       new age threshold (if not zero)
+    partitions          new number of partitions in the key cache 
+
+  DESCRIPTION
+    The function operates over the key cache keycache.
+    The parameter partitions specifies the number of partitions in the key
+    cache after repartitioning. If the value of this parameter is 0 then
+    a simple key cache must be created instead of the old one. 
+    The parameter key_cache_block_size specifies the new size of the block
+    buffers in the key cache. The parameters division_limit and age_threshold
+    determine the new initial values of those characteristics of the key cache
+    that are used for midpoint insertion strategy. The parameter use_mem
+    specifies the total amount of  memory to be allocated for the new key
+    cache buffers and for all auxiliary structures.
+
+  RETURN VALUE
+    number of blocks in the key cache, if successful,
+    0 - otherwise.
+
+  NOTES
+    The function does not block the calls and executions of other functions
+    from the key cache interface. However it assumes that the calls of 
+    resize_key_cache itself are serialized.
+
+    Currently the function is called when the value of the variable
+    key_cache_partitions is being reset for the key cache keycache.
+*/
+
+int repartition_key_cache(KEY_CACHE *keycache, uint key_cache_block_size,
+		          size_t use_mem, uint division_limit,
+                          uint age_threshold, uint partitions)
+{
+  uint blocks= -1;
+  if (keycache->key_cache_inited)
+  {
+    keycache->interface_funcs->resize(keycache->keycache_cb,
+                                      key_cache_block_size, 0,
+                                      division_limit, age_threshold);
+    end_key_cache(keycache, 1);
+    blocks= init_key_cache(keycache, key_cache_block_size, use_mem,
+                           division_limit, age_threshold, partitions);
+  } 
+  return blocks;
+}
+
diff --git a/sql/handler.cc b/sql/handler.cc
index f6b05a89ec1..28d898e1614 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -3826,11 +3826,13 @@ int ha_init_key_cache(const char *name, KEY_CACHE *key_cache)
     uint tmp_block_size= (uint) key_cache->param_block_size;
     uint division_limit= key_cache->param_division_limit;
     uint age_threshold=  key_cache->param_age_threshold;
+    uint partitions= key_cache->param_partitions;
     pthread_mutex_unlock(&LOCK_global_system_variables);
     DBUG_RETURN(!init_key_cache(key_cache,
 				tmp_block_size,
 				tmp_buff_size,
-				division_limit, age_threshold));
+				division_limit, age_threshold,
+                                partitions));
   }
   DBUG_RETURN(0);
 }
@@ -3860,10 +3862,12 @@ int ha_resize_key_cache(KEY_CACHE *key_cache)
 
 
 /**
-  Change parameters for key cache (like size)
+  Change parameters for key cache (like division_limit)
 */
 int ha_change_key_cache_param(KEY_CACHE *key_cache)
 {
+  DBUG_ENTER("ha_change_key_cache_param");
+
   if (key_cache->key_cache_inited)
   {
     pthread_mutex_lock(&LOCK_global_system_variables);
@@ -3872,9 +3876,35 @@ int ha_change_key_cache_param(KEY_CACHE *key_cache)
     pthread_mutex_unlock(&LOCK_global_system_variables);
     change_key_cache_param(key_cache, division_limit, age_threshold);
   }
-  return 0;
+  DBUG_RETURN(0);
 }
 
+
+/**
+  Repartition key cache 
+*/
+int ha_repartition_key_cache(KEY_CACHE *key_cache)
+{
+  DBUG_ENTER("ha_repartition_key_cache");
+
+  if (key_cache->key_cache_inited)
+  {
+    pthread_mutex_lock(&LOCK_global_system_variables);
+    size_t tmp_buff_size= (size_t) key_cache->param_buff_size;
+    long tmp_block_size= (long) key_cache->param_block_size;
+    uint division_limit= key_cache->param_division_limit;
+    uint age_threshold=  key_cache->param_age_threshold;
+    uint partitions= key_cache->param_partitions;
+    pthread_mutex_unlock(&LOCK_global_system_variables);
+    DBUG_RETURN(!repartition_key_cache(key_cache, tmp_block_size,
+				       tmp_buff_size,
+				       division_limit, age_threshold,
+                                       partitions));
+  }
+  DBUG_RETURN(0);
+}
+
+
 /**
   Free memory allocated by a key cache.
 */
diff --git a/sql/handler.h b/sql/handler.h
index f2061a69587..0df20a2b769 100644
--- a/sql/handler.h
+++ b/sql/handler.h
@@ -2201,6 +2201,7 @@ int ha_table_exists_in_engine(THD* thd, const char* db, const char* name);
 extern "C" int ha_init_key_cache(const char *name, KEY_CACHE *key_cache);
 int ha_resize_key_cache(KEY_CACHE *key_cache);
 int ha_change_key_cache_param(KEY_CACHE *key_cache);
+int ha_repartition_key_cache(KEY_CACHE *key_cache);
 int ha_change_key_cache(KEY_CACHE *old_key_cache, KEY_CACHE *new_key_cache);
 int ha_end_key_cache(KEY_CACHE *key_cache);
 
diff --git a/sql/mysqld.cc b/sql/mysqld.cc
index f991cceb3fd..f6bad3cf337 100644
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -5831,6 +5831,7 @@ enum options_mysqld
   OPT_INTERACTIVE_TIMEOUT, OPT_JOIN_BUFF_SIZE,
   OPT_KEY_BUFFER_SIZE, OPT_KEY_CACHE_BLOCK_SIZE,
   OPT_KEY_CACHE_DIVISION_LIMIT, OPT_KEY_CACHE_AGE_THRESHOLD,
+  OPT_KEY_CACHE_PARTITIONS,
   OPT_LONG_QUERY_TIME,
   OPT_LOWER_CASE_TABLE_NAMES, OPT_MAX_ALLOWED_PACKET,
   OPT_MAX_BINLOG_CACHE_SIZE, OPT_MAX_BINLOG_SIZE,
@@ -6928,6 +6929,12 @@ log and this option does nothing anymore.",
    (uchar**) 0,
    0, (GET_ULONG | GET_ASK_ADDR) , REQUIRED_ARG, 100,
    1, 100, 0, 1, 0},
+  {"key_cache_partitions", OPT_KEY_CACHE_PARTITIONS,
+   "The number of partitions in key cache",
+   (uchar**) &dflt_key_cache_var.param_partitions,
+   (uchar**) 0,
+   0, (GET_ULONG | GET_ASK_ADDR), REQUIRED_ARG, DEFAULT_KEY_CACHE_PARTITIONS,
+   0, MAX_KEY_CACHE_PARTITIONS, 0, 1, 0},  
   {"log-slow-filter", OPT_LOG_SLOW_FILTER,
    "Log only the queries that followed certain execution plan. Multiple flags allowed in a comma-separated string. [admin, filesort, filesort_on_disk, full_join, full_scan, query_cache, query_cache_miss, tmp_table, tmp_table_on_disk]. Sets log-slow-admin-command to ON",
    0, 0, 0, GET_STR, REQUIRED_ARG, 0, 0, 0, QPLAN_ALWAYS_SET, 0, 0},
@@ -8910,6 +8917,7 @@ mysql_getopt_value(const char *keyname, uint key_length,
   case OPT_KEY_CACHE_BLOCK_SIZE:
   case OPT_KEY_CACHE_DIVISION_LIMIT:
   case OPT_KEY_CACHE_AGE_THRESHOLD:
+  case OPT_KEY_CACHE_PARTITIONS:
   {
     KEY_CACHE *key_cache;
     if (!(key_cache= get_or_create_key_cache(keyname, key_length)))
@@ -8927,6 +8935,8 @@ mysql_getopt_value(const char *keyname, uint key_length,
       return (uchar**) &key_cache->param_division_limit;
     case OPT_KEY_CACHE_AGE_THRESHOLD:
       return (uchar**) &key_cache->param_age_threshold;
+    case OPT_KEY_CACHE_PARTITIONS:
+      return (uchar**) &key_cache->param_partitions;
     }
   }
   }
diff --git a/sql/set_var.cc b/sql/set_var.cc
index 545b086865f..e63c93f32ef 100644
--- a/sql/set_var.cc
+++ b/sql/set_var.cc
@@ -320,15 +320,18 @@ static sys_var_thd_ulong	sys_interactive_timeout(&vars, "interactive_timeout",
 static sys_var_thd_ulong	sys_join_buffer_size(&vars, "join_buffer_size",
 					     &SV::join_buff_size);
 static sys_var_key_buffer_size	sys_key_buffer_size(&vars, "key_buffer_size");
-static sys_var_key_cache_long  sys_key_cache_block_size(&vars, "key_cache_block_size",
-						 offsetof(KEY_CACHE,
-							  param_block_size));
-static sys_var_key_cache_long	sys_key_cache_division_limit(&vars, "key_cache_division_limit",
-						     offsetof(KEY_CACHE,
-							      param_division_limit));
-static sys_var_key_cache_long  sys_key_cache_age_threshold(&vars, "key_cache_age_threshold",
-						     offsetof(KEY_CACHE,
-							      param_age_threshold));
+static sys_var_key_cache_long  sys_key_cache_block_size(&vars,
+                                   "key_cache_block_size",
+                                   offsetof(KEY_CACHE,param_block_size));
+static sys_var_key_cache_long  sys_key_cache_division_limit(&vars,
+                                   "key_cache_division_limit",
+                                   offsetof(KEY_CACHE, param_division_limit));
+static sys_var_key_cache_long  sys_key_cache_age_threshold(&vars,
+                                   "key_cache_age_threshold",
+                                   offsetof(KEY_CACHE, param_age_threshold));
+static sys_var_key_cache_long  sys_key_cache_partitions(&vars,
+                                   "key_cache_partitions",
+                                   offsetof(KEY_CACHE, param_partitions));
 static sys_var_const    sys_language(&vars, "language",
                                      OPT_GLOBAL, SHOW_CHAR,
                                      (uchar*) language);
@@ -2548,7 +2551,21 @@ bool sys_var_key_cache_long::update(THD *thd, set_var *var)
 
   pthread_mutex_unlock(&LOCK_global_system_variables);
 
-  error= (bool) (ha_resize_key_cache(key_cache));
+  switch (offset) {
+
+  case  offsetof(KEY_CACHE, param_block_size):
+    error= (bool) (ha_resize_key_cache(key_cache));
+    break;
+
+  case offsetof(KEY_CACHE, param_division_limit):
+  case offsetof(KEY_CACHE, param_age_threshold):
+    error= (bool) (ha_change_key_cache_param(key_cache));
+    break;
+
+  case offsetof(KEY_CACHE, param_partitions):
+    error= (bool) (ha_repartition_key_cache(key_cache));
+    break;
+  }
 
   pthread_mutex_lock(&LOCK_global_system_variables);
   key_cache->in_init= 0;  
@@ -4156,6 +4173,7 @@ static KEY_CACHE *create_key_cache(const char *name, uint length)
       key_cache->param_block_size=     dflt_key_cache_var.param_block_size;
       key_cache->param_division_limit= dflt_key_cache_var.param_division_limit;
       key_cache->param_age_threshold=  dflt_key_cache_var.param_age_threshold;
+      key_cache->param_partitions=     dflt_key_cache_var.param_partitions;
     }
   }
   DBUG_RETURN(key_cache);
diff --git a/sql/set_var.h b/sql/set_var.h
index 5b4760589af..5b8fa1358cb 100644
--- a/sql/set_var.h
+++ b/sql/set_var.h
@@ -1427,6 +1427,7 @@ public:
     my_free((uchar*) name, MYF(0));
   }
   friend bool process_key_caches(process_key_cache_t func);
+  friend int fill_key_cache_tables(THD *thd, TABLE_LIST *tables, COND *cond);
   friend void delete_elements(I_List<NAMED_LIST> *list,
 			      void (*free_element)(const char*, uchar*));
 };
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index 6e991eba2f8..16eedc4aa5a 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -2249,6 +2249,32 @@ void remove_status_vars(SHOW_VAR *list)
 }
 
 
+
+static void update_key_cache_stat_var(KEY_CACHE *key_cache, size_t ofs)
+{
+  uint var_no;
+  switch (ofs) {
+  case offsetof(KEY_CACHE, blocks_used):
+  case offsetof(KEY_CACHE, blocks_unused): 
+  case offsetof(KEY_CACHE, global_blocks_changed):
+    var_no= (ofs-offsetof(KEY_CACHE, blocks_used))/sizeof(ulong);
+    *(ulong *)((char *) key_cache + ofs)=
+      (ulong) get_key_cache_stat_value(key_cache, var_no);
+    break; 
+  case offsetof(KEY_CACHE, global_cache_r_requests):
+  case offsetof(KEY_CACHE, global_cache_read):
+  case offsetof(KEY_CACHE, global_cache_w_requests):
+  case offsetof(KEY_CACHE, global_cache_write):
+    var_no= NUM_LONG_KEY_CACHE_STAT_VARIABLES +
+            (ofs-offsetof(KEY_CACHE, global_cache_w_requests))/
+             sizeof(ulonglong);
+    *(ulonglong *)((char *) key_cache + ofs)=
+      get_key_cache_stat_value(key_cache, var_no);
+    break;
+  } 
+}
+
+
 static bool show_status_array(THD *thd, const char *wild,
                               SHOW_VAR *variables,
                               enum enum_var_type value_type,
@@ -2381,10 +2407,12 @@ static bool show_status_array(THD *thd, const char *wild,
           break;
         }
         case SHOW_KEY_CACHE_LONG:
+          update_key_cache_stat_var(dflt_key_cache, (size_t) value);
           value= (char*) dflt_key_cache + (ulong)value;
           end= int10_to_str(*(long*) value, buff, 10);
           break;
         case SHOW_KEY_CACHE_LONGLONG:
+          update_key_cache_stat_var(dflt_key_cache, (size_t) value);
           value= (char*) dflt_key_cache + (ulong)value;
 	  end= longlong10_to_str(*(longlong*) value, buff, 10);
 	  break;
@@ -6640,6 +6668,90 @@ int fill_schema_files(THD *thd, TABLE_LIST *tables, COND *cond)
 }
 
 
+static
+int store_key_cache_table_record(THD *thd, TABLE *table,
+                                 const char *name, uint name_length,
+                                 KEY_CACHE *key_cache,
+                                 uint partitions, uint partition_no)
+{
+  KEY_CACHE_STATISTICS keycache_stats;
+  uint err;
+  DBUG_ENTER("store_key_cache_table_record");
+
+  get_key_cache_statistics(key_cache, partition_no, &keycache_stats);
+
+  if (!key_cache->key_cache_inited || keycache_stats.mem_size == 0)
+    DBUG_RETURN(0);
+
+  restore_record(table, s->default_values);
+  table->field[0]->store(name, name_length, system_charset_info);
+  if (partitions == 0)
+    table->field[1]->set_null();
+  else
+  {
+    table->field[1]->set_notnull(); 
+    table->field[1]->store((long) partitions, TRUE);
+  }
+
+  if (partition_no == 0)
+    table->field[2]->set_null();
+  else
+  {
+    table->field[2]->set_notnull();
+    table->field[2]->store((long) partition_no, TRUE);
+  }
+  table->field[3]->store(keycache_stats.mem_size, TRUE);
+  table->field[4]->store(keycache_stats.block_size, TRUE);
+  table->field[5]->store(keycache_stats.blocks_used, TRUE);
+  table->field[6]->store(keycache_stats.blocks_unused, TRUE);
+  table->field[7]->store(keycache_stats.blocks_changed, TRUE);
+  table->field[8]->store(keycache_stats.read_requests, TRUE);
+  table->field[9]->store(keycache_stats.reads, TRUE);
+  table->field[10]->store(keycache_stats.write_requests, TRUE);
+  table->field[11]->store(keycache_stats.writes, TRUE);
+
+  err= schema_table_store_record(thd, table);
+  DBUG_RETURN(err);
+}
+
+
+int fill_key_cache_tables(THD *thd, TABLE_LIST *tables, COND *cond)
+{
+  TABLE *table= tables->table;
+  I_List_iterator<NAMED_LIST> it(key_caches);
+  NAMED_LIST *element;
+  DBUG_ENTER("fill_key_cache_tables");
+
+  while ((element= it++))
+  {
+    KEY_CACHE *key_cache= (KEY_CACHE *) element->data;
+
+    if (!key_cache->key_cache_inited)
+      continue;
+
+    uint partitions= key_cache->partitions;    
+    DBUG_ASSERT(partitions <= MAX_KEY_CACHE_PARTITIONS);
+
+    if (partitions)
+    {
+      for (uint i= 0; i < partitions; i++)
+      {
+        if (store_key_cache_table_record(thd, table,
+                                         element->name, element->name_length, 
+                                         key_cache, partitions, i+1))
+	  DBUG_RETURN(1);
+      }
+    }
+
+    if (store_key_cache_table_record(thd, table, 
+                                     element->name, element->name_length,
+                                     key_cache, partitions, 0))
+      DBUG_RETURN(1);
+  }
+  DBUG_RETURN(0);
+}
+
+
 ST_FIELD_INFO schema_fields_info[]=
 {
   {"CATALOG_NAME", FN_REFLEN, MYSQL_TYPE_STRING, 0, 1, 0, SKIP_OPEN_TABLE},
@@ -7219,6 +7331,35 @@ ST_FIELD_INFO referential_constraints_fields_info[]=
 };
 
 
+ST_FIELD_INFO keycache_fields_info[]=
+{
+  {"KEY_CACHE_NAME", NAME_LEN, MYSQL_TYPE_STRING, 0, 0, 0, SKIP_OPEN_TABLE},
+  {"PARTITIONS", 3, MYSQL_TYPE_LONG, 0, 
+   (MY_I_S_MAYBE_NULL | MY_I_S_UNSIGNED) , 0, SKIP_OPEN_TABLE},
+  {"PARTITION_NUMBER", 3, MYSQL_TYPE_LONG, 0,
+   (MY_I_S_MAYBE_NULL | MY_I_S_UNSIGNED), 0, SKIP_OPEN_TABLE},
+  {"FULL_SIZE", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+   (MY_I_S_UNSIGNED), 0, SKIP_OPEN_TABLE},
+  {"BLOCK_SIZE", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+   (MY_I_S_UNSIGNED), 0, SKIP_OPEN_TABLE },
+  {"USED_BLOCKS", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+    (MY_I_S_UNSIGNED), "Key_blocks_used", SKIP_OPEN_TABLE},
+  {"UNUSED_BLOCKS", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+   (MY_I_S_UNSIGNED), "Key_blocks_unused", SKIP_OPEN_TABLE},
+  {"DIRTY_BLOCKS", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+   (MY_I_S_UNSIGNED), "Key_blocks_not_flushed", SKIP_OPEN_TABLE},
+  {"READ_REQUESTS", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+   (MY_I_S_UNSIGNED), "Key_read_requests", SKIP_OPEN_TABLE},
+  {"READS", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+   (MY_I_S_UNSIGNED), "Key_reads", SKIP_OPEN_TABLE},
+  {"WRITE_REQUESTS", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+   (MY_I_S_UNSIGNED), "Key_write_requests", SKIP_OPEN_TABLE},
+  {"WRITES", MY_INT64_NUM_DECIMAL_DIGITS, MYSQL_TYPE_LONGLONG, 0,
+   (MY_I_S_UNSIGNED), "Key_writes", SKIP_OPEN_TABLE},
+  {0, 0, MYSQL_TYPE_STRING, 0, 0, 0, SKIP_OPEN_TABLE}
+};
+
+
 /*
   Description of ST_FIELD_INFO in table.h
 
@@ -7258,6 +7399,8 @@ ST_SCHEMA_TABLE schema_tables[]=
    fill_variables, make_old_format, 0, 0, -1, 0, 0},
   {"INDEX_STATISTICS", index_stats_fields_info, create_schema_table,
    fill_schema_index_stats, make_old_format, 0, -1, -1, 0, 0},
+  {"KEY_CACHES", keycache_fields_info, create_schema_table,
+   fill_key_cache_tables, make_old_format, 0, -1,-1, 0, 0}, 
   {"KEY_COLUMN_USAGE", key_column_usage_fields_info, create_schema_table,
    get_all_tables, 0, get_schema_key_column_usage_record, 4, 5, 0,
    OPEN_TABLE_ONLY},
diff --git a/sql/sql_test.cc b/sql/sql_test.cc
index 5de8301fd05..5c9077f86ea 100644
--- a/sql/sql_test.cc
+++ b/sql/sql_test.cc
@@ -445,7 +445,8 @@ static int print_key_cache_status(const char *name, KEY_CACHE *key_cache)
 Buffer_size:    %10lu\n\
 Block_size:     %10lu\n\
 Division_limit: %10lu\n\
-Age_limit:      %10lu\n\
+Age_threshold:  %10lu\n\
+Partitions:     %10lu\n\
 blocks used:    %10lu\n\
 not flushed:    %10lu\n\
 w_requests:     %10s\n\
@@ -455,6 +456,7 @@ reads:          %10s\n\n",
 	   name,
 	   (ulong) key_cache->param_buff_size, key_cache->param_block_size,
 	   key_cache->param_division_limit, key_cache->param_age_threshold,
+           key_cache->param_partitions,
 	   key_cache->blocks_used,key_cache->global_blocks_changed,
 	   llstr(key_cache->global_cache_w_requests,llbuff1),
            llstr(key_cache->global_cache_write,llbuff2),
diff --git a/sql/table.h b/sql/table.h
index e258352b37b..3a82ce4531a 100644
--- a/sql/table.h
+++ b/sql/table.h
@@ -953,6 +953,7 @@ enum enum_schema_tables
   SCH_GLOBAL_STATUS,
   SCH_GLOBAL_VARIABLES,
   SCH_INDEX_STATS,
+  SCH_KEY_CACHES,
   SCH_KEY_COLUMN_USAGE,
   SCH_OPEN_TABLES,
   SCH_PARTITIONS,
diff --git a/storage/myisam/mi_check.c b/storage/myisam/mi_check.c
index 9fe954273fe..a13387b140d 100644
--- a/storage/myisam/mi_check.c
+++ b/storage/myisam/mi_check.c
@@ -332,7 +332,8 @@ int chk_size(HA_CHECK *param, register MI_INFO *info)
 
   /* The following is needed if called externally (not from myisamchk) */
   flush_key_blocks(info->s->key_cache,
-		   info->s->kfile, FLUSH_FORCE_WRITE);
+		   info->s->kfile, &info->s->dirty_part_map,
+                   FLUSH_FORCE_WRITE);
 
   size= my_seek(info->s->kfile, 0L, MY_SEEK_END, MYF(MY_THREADSAFE));
   if ((skr=(my_off_t) info->state->key_file_length) != size)
@@ -1474,6 +1475,7 @@ static int mi_drop_all_indexes(HA_CHECK *param, MI_INFO *info, my_bool force)
       */
       DBUG_PRINT("repair", ("all disabled are empty: create missing"));
       error= flush_key_blocks(share->key_cache, share->kfile,
+                              &share->dirty_part_map,
                               FLUSH_FORCE_WRITE);
       goto end;
     }
@@ -1488,6 +1490,7 @@ static int mi_drop_all_indexes(HA_CHECK *param, MI_INFO *info, my_bool force)
 
   /* Remove all key blocks of this index file from key cache. */
   if ((error= flush_key_blocks(share->key_cache, share->kfile,
+                               &share->dirty_part_map,
                                FLUSH_IGNORE_CHANGED)))
     goto end; /* purecov: inspected */
 
@@ -1549,7 +1552,7 @@ int mi_repair(HA_CHECK *param, register MI_INFO *info,
 
   if (!param->using_global_keycache)
     VOID(init_key_cache(dflt_key_cache, param->key_cache_block_size,
-                        (size_t) param->use_buffers, 0, 0));
+                        (size_t) param->use_buffers, 0, 0, 0));
 
   if (init_io_cache(&param->read_cache,info->dfile,
 		    (uint) param->read_buffer_length,
@@ -1762,7 +1765,8 @@ err:
   VOID(end_io_cache(&param->read_cache));
   info->opt_flag&= ~(READ_CACHE_USED | WRITE_CACHE_USED);
   VOID(end_io_cache(&info->rec_cache));
-  got_error|=flush_blocks(param, share->key_cache, share->kfile);
+  got_error|=flush_blocks(param, share->key_cache, share->kfile,
+                          &share->dirty_part_map);
   if (!got_error && param->testflag & T_UNPACK)
   {
     share->state.header.options[0]&= (uchar) ~HA_OPTION_COMPRESS_RECORD;
@@ -1908,9 +1912,10 @@ void lock_memory(HA_CHECK *param __attribute__((unused)))
 
 	/* Flush all changed blocks to disk */
 
-int flush_blocks(HA_CHECK *param, KEY_CACHE *key_cache, File file)
+int flush_blocks(HA_CHECK *param, KEY_CACHE *key_cache, File file,
+                 ulonglong *dirty_part_map)
 {
-  if (flush_key_blocks(key_cache, file, FLUSH_RELEASE))
+  if (flush_key_blocks(key_cache, file, dirty_part_map, FLUSH_RELEASE))
   {
     mi_check_print_error(param,"%d when trying to write bufferts",my_errno);
     return(1);
@@ -1977,7 +1982,8 @@ int mi_sort_index(HA_CHECK *param, register MI_INFO *info, char * name)
   }
 
   /* Flush key cache for this file if we are calling this outside myisamchk */
-  flush_key_blocks(share->key_cache,share->kfile, FLUSH_IGNORE_CHANGED);
+  flush_key_blocks(share->key_cache, share->kfile, &share->dirty_part_map,
+                   FLUSH_IGNORE_CHANGED);
 
   share->state.version=(ulong) time((time_t*) 0);
   old_state= share->state;			/* save state if not stored */
@@ -2535,7 +2541,8 @@ int mi_repair_by_sort(HA_CHECK *param, register MI_INFO *info,
     memcpy( &share->state.state, info->state, sizeof(*info->state));
 
 err:
-  got_error|= flush_blocks(param, share->key_cache, share->kfile);
+  got_error|= flush_blocks(param, share->key_cache, share->kfile,
+                           &share->dirty_part_map);
   VOID(end_io_cache(&info->rec_cache));
   if (!got_error)
   {
@@ -3059,7 +3066,8 @@ int mi_repair_parallel(HA_CHECK *param, register MI_INFO *info,
     memcpy(&share->state.state, info->state, sizeof(*info->state));
 
 err:
-  got_error|= flush_blocks(param, share->key_cache, share->kfile);
+  got_error|= flush_blocks(param, share->key_cache, share->kfile,
+                           &share->dirty_part_map);
   /*
     Destroy the write cache. The master thread did already detach from
     the share by remove_io_thread() or it was not yet started (if the
diff --git a/storage/myisam/mi_close.c b/storage/myisam/mi_close.c
index fbd24237286..a8d678494f5 100644
--- a/storage/myisam/mi_close.c
+++ b/storage/myisam/mi_close.c
@@ -64,6 +64,7 @@ int mi_close(register MI_INFO *info)
                     if (share->kfile >= 0) abort(););
     if (share->kfile >= 0 &&
 	flush_key_blocks(share->key_cache, share->kfile,
+                         &share->dirty_part_map,
                          ((share->temporary || share->deleting) ?
                           FLUSH_IGNORE_CHANGED :
                           FLUSH_RELEASE)))
diff --git a/storage/myisam/mi_delete_all.c b/storage/myisam/mi_delete_all.c
index e2bbb04ab3c..18fcdee77e2 100644
--- a/storage/myisam/mi_delete_all.c
+++ b/storage/myisam/mi_delete_all.c
@@ -52,7 +52,8 @@ int mi_delete_all_rows(MI_INFO *info)
     If we are using delayed keys or if the user has done changes to the tables
     since it was locked then there may be key blocks in the key cache
   */
-  flush_key_blocks(share->key_cache, share->kfile, FLUSH_IGNORE_CHANGED);
+  flush_key_blocks(share->key_cache, share->kfile, &share->dirty_part_map,
+                   FLUSH_IGNORE_CHANGED);
 #ifdef HAVE_MMAP
   if (share->file_map)
     _mi_unmap_file(info);
diff --git a/storage/myisam/mi_extra.c b/storage/myisam/mi_extra.c
index 64e7a55231d..32516d0115e 100644
--- a/storage/myisam/mi_extra.c
+++ b/storage/myisam/mi_extra.c
@@ -268,6 +268,7 @@ int mi_extra(MI_INFO *info, enum ha_extra_function function, void *extra_arg)
     pthread_mutex_lock(&share->intern_lock);
     /* Flush pages that we don't need anymore */
     if (flush_key_blocks(share->key_cache, share->kfile,
+                         &share->dirty_part_map,
 			 (function == HA_EXTRA_PREPARE_FOR_DROP ?
                           FLUSH_IGNORE_CHANGED : FLUSH_RELEASE)))
     {
@@ -326,7 +327,8 @@ int mi_extra(MI_INFO *info, enum ha_extra_function function, void *extra_arg)
     break;
   case HA_EXTRA_FLUSH:
     if (!share->temporary)
-      flush_key_blocks(share->key_cache, share->kfile, FLUSH_KEEP);
+      flush_key_blocks(share->key_cache, share->kfile, &share->dirty_part_map,
+                       FLUSH_KEEP);
 #ifdef HAVE_PWRITE
     _mi_decrement_open_count(info);
 #endif
diff --git a/storage/myisam/mi_keycache.c b/storage/myisam/mi_keycache.c
index 5cf3fede1ae..be0cdc470f1 100644
--- a/storage/myisam/mi_keycache.c
+++ b/storage/myisam/mi_keycache.c
@@ -75,7 +75,8 @@ int mi_assign_to_key_cache(MI_INFO *info,
     in the old key cache.
   */
 
-  if (flush_key_blocks(share->key_cache, share->kfile, FLUSH_RELEASE))
+  if (flush_key_blocks(share->key_cache, share->kfile, &share->dirty_part_map,
+                       FLUSH_RELEASE))
   {
     error= my_errno;
     mi_print_error(info->s, HA_ERR_CRASHED);
@@ -90,7 +91,8 @@ int mi_assign_to_key_cache(MI_INFO *info,
     (This can never fail as there is never any not written data in the
     new key cache)
   */
-  (void) flush_key_blocks(key_cache, share->kfile, FLUSH_RELEASE);
+  (void) flush_key_blocks(key_cache, share->kfile, &share->dirty_part_map,
+                          FLUSH_RELEASE);
 
   /*
     ensure that setting the key cache and changing the multi_key_cache
@@ -102,6 +104,7 @@ int mi_assign_to_key_cache(MI_INFO *info,
     This should be seen at the lastes for the next call to an myisam function.
   */
   share->key_cache= key_cache;
+  share->dirty_part_map= 0;
 
   /* store the key cache in the global hash structure for future opens */
   if (multi_key_cache_set((uchar*) share->unique_file_name,
diff --git a/storage/myisam/mi_locking.c b/storage/myisam/mi_locking.c
index b935d517c81..a76790c7d7d 100644
--- a/storage/myisam/mi_locking.c
+++ b/storage/myisam/mi_locking.c
@@ -68,7 +68,9 @@ int mi_lock_database(MI_INFO *info, int lock_type)
       --share->tot_locks;
       if (info->lock_type == F_WRLCK && !share->w_locks &&
 	  !share->delay_key_write && flush_key_blocks(share->key_cache,
-						      share->kfile,FLUSH_KEEP))
+						      share->kfile,
+                                                      &share->dirty_part_map,
+                                                      FLUSH_KEEP))
       {
 	error=my_errno;
         mi_print_error(info->s, HA_ERR_CRASHED);
@@ -513,7 +515,8 @@ int _mi_test_if_changed(register MI_INFO *info)
   {						/* Keyfile has changed */
     DBUG_PRINT("info",("index file changed"));
     if (share->state.process != share->this_process)
-      VOID(flush_key_blocks(share->key_cache, share->kfile, FLUSH_RELEASE));
+      VOID(flush_key_blocks(share->key_cache, share->kfile,
+                            &share->dirty_part_map, FLUSH_RELEASE));
     share->last_process=share->state.process;
     info->last_unique=	share->state.unique;
     info->last_loop=	share->state.update_count;
diff --git a/storage/myisam/mi_page.c b/storage/myisam/mi_page.c
index a05a96e514b..70a26c5ba25 100644
--- a/storage/myisam/mi_page.c
+++ b/storage/myisam/mi_page.c
@@ -94,10 +94,11 @@ int _mi_write_keypage(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   }
 #endif
   DBUG_RETURN((key_cache_write(info->s->key_cache,
-                         info->s->kfile,page, level, (uchar*) buff,length,
-			 (uint) keyinfo->block_length,
-			 (int) ((info->lock_type != F_UNLCK) ||
-				info->s->delay_key_write))));
+			       info->s->kfile, &info->s->dirty_part_map,
+                               page, level, (uchar*) buff, length,
+			       (uint) keyinfo->block_length,
+			       (int) ((info->lock_type != F_UNLCK) ||
+				     info->s->delay_key_write))));
 } /* mi_write_keypage */
 
 
@@ -116,7 +117,8 @@ int _mi_dispose(register MI_INFO *info, MI_KEYDEF *keyinfo, my_off_t pos,
   mi_sizestore(buff,old_link);
   info->s->state.changed|= STATE_NOT_SORTED_PAGES;
   DBUG_RETURN(key_cache_write(info->s->key_cache,
-                              info->s->kfile, pos , level, buff,
+                              info->s->kfile, &info->s->dirty_part_map,
+                              pos , level, buff,
 			      sizeof(buff),
 			      (uint) keyinfo->block_length,
 			      (int) (info->lock_type != F_UNLCK)));
diff --git a/storage/myisam/mi_panic.c b/storage/myisam/mi_panic.c
index 74c93761b61..2d06b66f834 100644
--- a/storage/myisam/mi_panic.c
+++ b/storage/myisam/mi_panic.c
@@ -47,7 +47,8 @@ int mi_panic(enum ha_panic_function flag)
       if (info->s->options & HA_OPTION_READ_ONLY_DATA)
 	break;
 #endif
-      if (flush_key_blocks(info->s->key_cache, info->s->kfile, FLUSH_RELEASE))
+      if (flush_key_blocks(info->s->key_cache, info->s->kfile,
+                           &info->s->dirty_part_map, FLUSH_RELEASE))
 	error=my_errno;
       if (info->opt_flag & WRITE_CACHE_USED)
 	if (flush_io_cache(&info->rec_cache))
diff --git a/storage/myisam/mi_preload.c b/storage/myisam/mi_preload.c
index 60ab55106cb..115f0f0c70c 100644
--- a/storage/myisam/mi_preload.c
+++ b/storage/myisam/mi_preload.c
@@ -65,7 +65,7 @@ int mi_preload(MI_INFO *info, ulonglong key_map, my_bool ignore_leaves)
     }
   }
   else
-    block_length= share->key_cache->key_cache_block_size;
+    block_length= share->key_cache->param_block_size;
 
   length= info->preload_buff_size/block_length * block_length;
   set_if_bigger(length, block_length);
@@ -73,7 +73,8 @@ int mi_preload(MI_INFO *info, ulonglong key_map, my_bool ignore_leaves)
   if (!(buff= (uchar *) my_malloc(length, MYF(MY_WME))))
     DBUG_RETURN(my_errno= HA_ERR_OUT_OF_MEM);
 
-  if (flush_key_blocks(share->key_cache,share->kfile, FLUSH_RELEASE))
+  if (flush_key_blocks(share->key_cache, share->kfile, &share->dirty_part_map,
+                       FLUSH_RELEASE))
     goto err;
 
   do
diff --git a/storage/myisam/mi_test1.c b/storage/myisam/mi_test1.c
index 8e491823939..aea8d86e380 100644
--- a/storage/myisam/mi_test1.c
+++ b/storage/myisam/mi_test1.c
@@ -49,7 +49,8 @@ int main(int argc,char *argv[])
   MY_INIT(argv[0]);
   my_init();
   if (key_cacheing)
-    init_key_cache(dflt_key_cache,KEY_CACHE_BLOCK_SIZE,IO_SIZE*16,0,0);
+    init_key_cache(dflt_key_cache,KEY_CACHE_BLOCK_SIZE,IO_SIZE*16,0,0,
+                   DEFAULT_KEY_CACHE_PARTITIONS);
   get_options(argc,argv);
 
   exit(run_test("test1"));
diff --git a/storage/myisam/mi_test2.c b/storage/myisam/mi_test2.c
index 9844126e7dd..67da89e55ef 100644
--- a/storage/myisam/mi_test2.c
+++ b/storage/myisam/mi_test2.c
@@ -215,7 +215,8 @@ int main(int argc, char *argv[])
   if (!silent)
     printf("- Writing key:s\n");
   if (key_cacheing)
-    init_key_cache(dflt_key_cache,key_cache_block_size,key_cache_size,0,0);
+    init_key_cache(dflt_key_cache,key_cache_block_size,key_cache_size,0,0,
+                   DEFAULT_KEY_CACHE_PARTITIONS);
   if (do_locking)
     mi_lock_database(file,F_WRLCK);
   if (write_cacheing)
diff --git a/storage/myisam/mi_test3.c b/storage/myisam/mi_test3.c
index e792612a313..e4527bf441d 100644
--- a/storage/myisam/mi_test3.c
+++ b/storage/myisam/mi_test3.c
@@ -177,7 +177,8 @@ void start_test(int id)
     exit(1);
   }
   if (key_cacheing && rnd(2) == 0)
-    init_key_cache(dflt_key_cache, KEY_CACHE_BLOCK_SIZE, 65536L, 0, 0);
+    init_key_cache(dflt_key_cache, KEY_CACHE_BLOCK_SIZE, 65536L, 0, 0,
+                   DEFAULT_KEY_CACHE_PARTITIONS);
   printf("Process %d, pid: %ld\n", id, (long) getpid());
   fflush(stdout);
 
diff --git a/storage/myisam/myisam_ftdump.c b/storage/myisam/myisam_ftdump.c
index 3eecb08bd99..4436d06e36b 100644
--- a/storage/myisam/myisam_ftdump.c
+++ b/storage/myisam/myisam_ftdump.c
@@ -83,7 +83,7 @@ int main(int argc,char *argv[])
       usage();
   }
 
-  init_key_cache(dflt_key_cache,MI_KEY_BLOCK_LENGTH,USE_BUFFER_INIT, 0, 0);
+  init_key_cache(dflt_key_cache,MI_KEY_BLOCK_LENGTH,USE_BUFFER_INIT, 0, 0, 0);
 
   if (!(info=mi_open(argv[0], O_RDONLY,
                      HA_OPEN_ABORT_IF_LOCKED|HA_OPEN_FROM_SQL_LAYER)))
diff --git a/storage/myisam/myisamchk.c b/storage/myisam/myisamchk.c
index f8dd3b9c51f..d5d1c548717 100644
--- a/storage/myisam/myisamchk.c
+++ b/storage/myisam/myisamchk.c
@@ -1102,7 +1102,7 @@ static int myisamchk(HA_CHECK *param, char * filename)
       {
 	if (param->testflag & (T_EXTEND | T_MEDIUM))
 	  VOID(init_key_cache(dflt_key_cache,opt_key_cache_block_size,
-                              (size_t) param->use_buffers, 0, 0));
+                              (size_t) param->use_buffers, 0, 0, 0));
 	VOID(init_io_cache(&param->read_cache,datafile,
 			   (uint) param->read_buffer_length,
 			   READ_CACHE,
@@ -1116,7 +1116,8 @@ static int myisamchk(HA_CHECK *param, char * filename)
 				 HA_OPTION_COMPRESS_RECORD)) ||
 	    (param->testflag & (T_EXTEND | T_MEDIUM)))
 	  error|=chk_data_link(param, info, test(param->testflag & T_EXTEND));
-	error|=flush_blocks(param, share->key_cache, share->kfile);
+	error|=flush_blocks(param, share->key_cache, share->kfile,
+                            &share->dirty_part_map);
 	VOID(end_io_cache(&param->read_cache));
       }
       if (!error)
@@ -1526,7 +1527,7 @@ static int mi_sort_records(HA_CHECK *param,
     DBUG_RETURN(0);				/* Nothing to do */
 
   init_key_cache(dflt_key_cache, opt_key_cache_block_size,
-                 (size_t) param->use_buffers, 0, 0);
+                 (size_t) param->use_buffers, 0, 0, 0);
   if (init_io_cache(&info->rec_cache,-1,(uint) param->write_buffer_length,
 		   WRITE_CACHE,share->pack.header_length,1,
 		   MYF(MY_WME | MY_WAIT_IF_FULL)))
@@ -1641,8 +1642,8 @@ err:
   my_free(sort_info.buff,MYF(MY_ALLOW_ZERO_PTR));
   sort_info.buff=0;
   share->state.sortkey=sort_key;
-  DBUG_RETURN(flush_blocks(param, share->key_cache, share->kfile) |
-	      got_error);
+  DBUG_RETURN(flush_blocks(param, share->key_cache, share->kfile,
+                           &share->dirty_part_map) | got_error);
 } /* sort_records */
 
 
diff --git a/storage/myisam/myisamdef.h b/storage/myisam/myisamdef.h
index 7eb7089f38c..c003048e07e 100644
--- a/storage/myisam/myisamdef.h
+++ b/storage/myisam/myisamdef.h
@@ -174,6 +174,8 @@ typedef struct st_mi_isam_share
    *index_file_name;
   uchar *file_map;                       /* mem-map of file if possible */
   KEY_CACHE *key_cache;                 /* ref to the current key cache */
+  /* To mark the key cache partitions containing dirty pages for this file */ 
+  ulonglong dirty_part_map;   
   MI_DECODE_TREE *decode_trees;
   uint16 *decode_tables;
   /* Function to use for a row checksum. */
@@ -732,7 +734,8 @@ void mi_check_print_info _VARARGS((HA_CHECK *param, const char *fmt, ...));
 #ifdef THREAD
 pthread_handler_t thr_find_all_keys(void *arg);
 #endif
-int flush_blocks(HA_CHECK *param, KEY_CACHE *key_cache, File file);
+int flush_blocks(HA_CHECK *param, KEY_CACHE *key_cache, File file,
+                 ulonglong *dirty_part_map);
 #ifdef __cplusplus
 }
 #endif
diff --git a/storage/myisam/myisamlog.c b/storage/myisam/myisamlog.c
index 679dc0b731b..8b4ccfe3256 100644
--- a/storage/myisam/myisamlog.c
+++ b/storage/myisam/myisamlog.c
@@ -333,7 +333,7 @@ static int examine_log(char * file_name, char **table_names)
   init_tree(&tree,0,0,sizeof(file_info),(qsort_cmp2) file_info_compare,1,
 	    (tree_element_free) file_info_free, NULL);
   VOID(init_key_cache(dflt_key_cache,KEY_CACHE_BLOCK_SIZE,KEY_CACHE_SIZE,
-                      0, 0));
+                      0, 0, 0));
 
   files_open=0; access_time=0;
   while (access_time++ != number_of_commands &&