diff options
Diffstat (limited to 'sql')
| -rw-r--r-- | sql/ha_heap.cc | 56 | ||||
| -rw-r--r-- | sql/ha_heap.h | 10 | ||||
| -rw-r--r-- | sql/structs.h | 7 |
3 files changed, 64 insertions, 9 deletions
diff --git a/sql/ha_heap.cc b/sql/ha_heap.cc index d7327362286..7643037e24f 100644 --- a/sql/ha_heap.cc +++ b/sql/ha_heap.cc @@ -30,6 +30,12 @@ const char **ha_heap::bas_ext() const { static const char *ext[1]= { NullS }; return ext; } +/* + Hash index statistics is updated (copied from HP_KEYDEF::hash_buckets to + rec_per_key) after 1/HEAP_STATS_UPDATE_THRESHOLD records have been inserted/ + updated/deleted. delete_all_rows() and table flush cause immediate update. +*/ +#define HEAP_STATS_UPDATE_THRESHOLD 10 int ha_heap::open(const char *name, int mode, uint test_if_locked) { @@ -48,6 +54,8 @@ int ha_heap::open(const char *name, int mode, uint test_if_locked) { /* Initialize variables for the opened table */ set_keys_for_scanning(); + if (table->tmp_table == NO_TMP_TABLE) + update_key_stats(); } return (file ? 0 : 1); } @@ -84,28 +92,59 @@ void ha_heap::set_keys_for_scanning(void) } } +void ha_heap::update_key_stats() +{ + printf("update_key_stats\n"); + for (uint i= 0; i < table->keys; i++) + { + KEY *key=table->key_info+i; + if (key->algorithm != HA_KEY_ALG_BTREE) + { + ha_rows hash_buckets= file->s->keydef[i].hash_buckets; + key->rec_per_key[key->key_parts-1]= + hash_buckets ? file->s->records/hash_buckets : 0; + } + } + records_changed= 0; +} + int ha_heap::write_row(byte * buf) { + int res; statistic_increment(ha_write_count,&LOCK_status); if (table->timestamp_default_now) update_timestamp(buf+table->timestamp_default_now-1); if (table->next_number_field && buf == table->record[0]) update_auto_increment(); - return heap_write(file,buf); + res= heap_write(file,buf); + if (!res && table->tmp_table == NO_TMP_TABLE && + ++records_changed*HEAP_STATS_UPDATE_THRESHOLD > file->s->records) + update_key_stats(); + return res; } int ha_heap::update_row(const byte * old_data, byte * new_data) { + int res; statistic_increment(ha_update_count,&LOCK_status); if (table->timestamp_on_update_now) update_timestamp(new_data+table->timestamp_on_update_now-1); - return heap_update(file,old_data,new_data); + res= heap_update(file,old_data,new_data); + if (!res && table->tmp_table == NO_TMP_TABLE && + ++records_changed*HEAP_STATS_UPDATE_THRESHOLD > file->s->records) + update_key_stats(); + return res; } int ha_heap::delete_row(const byte * buf) { + int res; statistic_increment(ha_delete_count,&LOCK_status); - return heap_delete(file,buf); + res= heap_delete(file,buf); + if (!res && table->tmp_table == NO_TMP_TABLE && + ++records_changed*HEAP_STATS_UPDATE_THRESHOLD > file->s->records) + update_key_stats(); + return res; } int ha_heap::index_read(byte * buf, const byte * key, uint key_len, @@ -227,6 +266,8 @@ int ha_heap::extra(enum ha_extra_function operation) int ha_heap::delete_all_rows() { heap_clear(file); + if (table->tmp_table == NO_TMP_TABLE) + update_key_stats(); return 0; } @@ -383,7 +424,14 @@ ha_rows ha_heap::records_in_range(uint inx, key_range *min_key, min_key->flag != HA_READ_KEY_EXACT || max_key->flag != HA_READ_AFTER_KEY) return HA_POS_ERROR; // Can only use exact keys - return 10; // Good guess + else + { + ha_rows records= file->s->records; + if (!records) + return 0; + ha_rows res= records / file->s->keydef[inx].hash_buckets; + return res ? res : 1; + } } diff --git a/sql/ha_heap.h b/sql/ha_heap.h index 9ca6b9b76b6..f36e9f31c55 100644 --- a/sql/ha_heap.h +++ b/sql/ha_heap.h @@ -27,9 +27,10 @@ class ha_heap: public handler { HP_INFO *file; key_map btree_keys; - - public: - ha_heap(TABLE *table): handler(table), file(0) {} + /* number of records changed since last statistics update */ + uint records_changed; +public: + ha_heap(TABLE *table): handler(table), file(0), records_changed(0) {} ~ha_heap() {} const char *table_type() const { return "HEAP"; } const char *index_type(uint inx) @@ -91,5 +92,6 @@ class ha_heap: public handler THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to, enum thr_lock_type lock_type); - +private: + void update_key_stats(); }; diff --git a/sql/structs.h b/sql/structs.h index c30d85f59cb..846b3400fab 100644 --- a/sql/structs.h +++ b/sql/structs.h @@ -89,7 +89,12 @@ typedef struct st_key { enum ha_key_alg algorithm; KEY_PART_INFO *key_part; char *name; /* Name of key */ - ulong *rec_per_key; /* Key part distribution */ + /* + Array of AVG(#records with the same field value) for 1st ... Nth key part. + 0 means 'not known'. + For temporary heap tables this member is NULL. + */ + ulong *rec_per_key; union { int bdb_return_if_eq; } handler; |