10.0-base merge

(without InnoDB - all InnoDB changes were ignored)

1 files changed, 41 insertions, 4 deletions

diff --git a/sql/sql_cache.cc b/sql/sql_cache.cc
index ba204f48978..436f7043c49 100644
--- a/sql/sql_cache.cc
+++ b/sql/sql_cache.cc
@@ -472,6 +472,8 @@ static void make_base_query(String *new_query,
   /* The following is guaranteed by the query_cache interface */
   DBUG_ASSERT(query[query_length] == 0);
   DBUG_ASSERT(!is_white_space(query[0]));
+  /* We do not support UCS2, UTF16, UTF32 as a client character set */
+  DBUG_ASSERT(current_thd->variables.character_set_client->mbminlen == 1);
 
   new_query->length(0);           // Don't copy anything from old buffer
   if (new_query->realloc(query_length + additional_length))
@@ -2439,7 +2441,28 @@ void Query_cache::init()
   m_cache_status= Query_cache::OK;
   m_requests_in_progress= 0;
   initialized = 1;
-  query_state_map= default_charset_info->state_map;
+  /*
+    Using state_map from latin1 should be fine in all cases:
+    1. We do not support UCS2, UTF16, UTF32 as a client character set.
+    2. The other character sets are compatible on the lower ASCII-range
+    0x00-0x20, and have the following characters marked as spaces:
+    
+    0x09 TAB
+    0x0A LINE FEED
+    0x0B VERTICAL TAB
+    0x0C FORM FEED
+    0x0D CARRIAGE RETUR
+    0x20 SPACE
+    
+    Additionally, only some of the ASCII-compatible character sets
+    (including latin1) can have 0xA0 mapped to "NON-BREAK SPACE"
+    and thus marked as space.
+    That should not be a problem for those charsets that map 0xA0
+    to something else: the parser will just return syntax error
+    if this character appears straight in the query
+    (i.e. not inside a string literal or comment).
+  */
+  query_state_map= my_charset_latin1.state_map;
   /*
     If we explicitly turn off query cache from the command line query
     cache will be disabled for the reminder of the server life
@@ -3972,6 +3995,18 @@ Query_cache::process_and_count_tables(THD *thd, TABLE_LIST *tables_used,
 
 
 /*
+In non-embedded QC intercepts result in net_real_write
+but if we have no net.vio then net_real_write
+will not be called, so QC can't get results of the query
+*/
+#ifdef EMBEDDED_LIBRARY
+#define qc_is_able_to_intercept_result(T) 1
+#else
+#define qc_is_able_to_intercept_result(T) ((T)->net.vio)
+#endif
+
+
+/*
   If query is cacheable return number tables in query
   (query without tables are not cached)
 */
@@ -3986,7 +4021,8 @@ Query_cache::is_cacheable(THD *thd, LEX *lex,
   if (thd->lex->safe_to_cache_query &&
       (thd->variables.query_cache_type == 1 ||
        (thd->variables.query_cache_type == 2 && (lex->select_lex.options &
-						 OPTION_TO_QUERY_CACHE))))
+						 OPTION_TO_QUERY_CACHE))) &&
+      qc_is_able_to_intercept_result(thd))
   {
     DBUG_PRINT("qcache", ("options: %lx  %lx  type: %u",
                           (long) OPTION_TO_QUERY_CACHE,
@@ -4008,11 +4044,12 @@ Query_cache::is_cacheable(THD *thd, LEX *lex,
   }
 
   DBUG_PRINT("qcache",
-	     ("not interesting query: %d or not cacheable, options %lx %lx  type: %u",
+	     ("not interesting query: %d or not cacheable, options %lx %lx  type: %u  net->vio present: %u",
 	      (int) lex->sql_command,
 	      (long) OPTION_TO_QUERY_CACHE,
 	      (long) lex->select_lex.options,
-	      (int) thd->variables.query_cache_type));
+	      (int) thd->variables.query_cache_type,
+              (uint) test(qc_is_able_to_intercept_result(thd))));
   DBUG_RETURN(0);
 }