Fix for BUG#8055 "Trouble with replication from temporary tables and ignores":

when we close the session's temp tables at session end, we automatically write to binlog *one* DROP TEMPORARY TABLE *per tmp table*.

mysql-test/r/drop_temp_table.result

 reset master;
 create database `drop-temp+table-test`;
 use `drop-temp+table-test`;
+create temporary table shortn1 (a int);
 create temporary table `table:name` (a int);
+create temporary table shortn2 (a int);
 select get_lock("a",10);
 get_lock("a",10)
 1
@@ -10,9 +12,13 @@ get_lock("a",10)
 1
 show binlog events;
 Log_name	Pos	Event_type	Server_id	Orig_log_pos	Info
-master-bin.000001	4	Start	1	4	Server ver: VERSION, Binlog ver: 3
-master-bin.000001	79	Query	1	79	create database `drop-temp+table-test`
-master-bin.000001	168	Query	1	168	use `drop-temp+table-test`; create temporary table `table:name` (a int)
-master-bin.000001	262	Query	1	262	use `drop-temp+table-test`; DROP /*!40005 TEMPORARY */ TABLE IF EXISTS `drop-temp+table-test`.`table:name`
-master-bin.000001	391	Query	1	391	use `drop-temp+table-test`; DO RELEASE_LOCK("a")
+master-bin.000001	#	Start	1	#	Server ver: VERSION, Binlog ver: 3
+master-bin.000001	#	Query	1	#	create database `drop-temp+table-test`
+master-bin.000001	#	Query	1	#	use `drop-temp+table-test`; create temporary table shortn1 (a int)
+master-bin.000001	#	Query	1	#	use `drop-temp+table-test`; create temporary table `table:name` (a int)
+master-bin.000001	#	Query	1	#	use `drop-temp+table-test`; create temporary table shortn2 (a int)
+master-bin.000001	#	Query	1	#	use `drop-temp+table-test`; DROP /*!40005 TEMPORARY */ TABLE IF EXISTS `drop-temp+table-test`.`shortn2`
+master-bin.000001	#	Query	1	#	use `drop-temp+table-test`; DROP /*!40005 TEMPORARY */ TABLE IF EXISTS `drop-temp+table-test`.`table:name`
+master-bin.000001	#	Query	1	#	use `drop-temp+table-test`; DROP /*!40005 TEMPORARY */ TABLE IF EXISTS `drop-temp+table-test`.`shortn1`
+master-bin.000001	#	Query	1	#	use `drop-temp+table-test`; DO RELEASE_LOCK("a")
 drop database `drop-temp+table-test`;

mysql-test/t/drop_temp_table.test

@@ -4,7 +4,9 @@ connection con1;
 reset master;
 create database `drop-temp+table-test`;
 use `drop-temp+table-test`;
+create temporary table shortn1 (a int);
 create temporary table `table:name` (a int);
+create temporary table shortn2 (a int);
 select get_lock("a",10);
 disconnect con1;
 
@@ -15,5 +17,6 @@ connection con2;
 select get_lock("a",10);
 let $VERSION=`select version()`;
 --replace_result $VERSION VERSION
+--replace_column 2 # 5 #
 show binlog events;
 drop database `drop-temp+table-test`;

sql/sql_base.cc

@@ -485,62 +485,58 @@ void close_temporary(TABLE *table,bool delete_table)
 void close_temporary_tables(THD *thd)
 {
   TABLE *table,*next;
-  char *query, *end;
-  uint query_buf_size; 
-  bool found_user_tables = 0;
+  char *query, *name_in_query, *end;
+  uint greatest_key_length= 0;
 
   if (!thd->temporary_tables)
     return;
   
+  /*
+    We write a DROP TEMPORARY TABLE for each temp table left, so that our
+    replication slave can clean them up. Not one multi-table DROP TABLE binlog
+    event: this would cause problems if slave uses --replicate-*-table.
+  */
   LINT_INIT(end);
-  query_buf_size= 50;   // Enough for DROP ... TABLE IF EXISTS
 
+  /* We'll re-use always same buffer so make it big enough for longest name */
   for (table=thd->temporary_tables ; table ; table=table->next)
-    /*
-      We are going to add 4 ` around the db/table names, so 1 does not look
-      enough; indeed it is enough, because table->key_length is greater (by 8,
-      because of server_id and thread_id) than db||table.
-    */
-    query_buf_size+= table->key_length+1;
+    greatest_key_length= max(greatest_key_length, table->key_length);
 
-  if ((query = alloc_root(thd->mem_root, query_buf_size)))
+  if ((query = alloc_root(thd->mem_root, greatest_key_length+50)))
     // Better add "if exists", in case a RESET MASTER has been done
-    end=strmov(query, "DROP /*!40005 TEMPORARY */ TABLE IF EXISTS ");
+    name_in_query= strmov(query, "DROP /*!40005 TEMPORARY */ TABLE IF EXISTS `");
 
   for (table=thd->temporary_tables ; table ; table=next)
   {
-    if (query) // we might be out of memory, but this is not fatal
+    /*
+      In we are OOM for 'query' this is not fatal. We skip temporary tables
+      not created directly by the user.
+    */
+    if (query && mysql_bin_log.is_open() && (table->real_name[0] != '#'))
     {
-      // skip temporary tables not created directly by the user
-      if (table->real_name[0] != '#')
-	found_user_tables = 1;
       /*
         Here we assume table_cache_key always starts
         with \0 terminated db name
       */
-      end = strxmov(end,"`",table->table_cache_key,"`.`",
-                    table->real_name,"`,", NullS);
+      end = strxmov(name_in_query, table->table_cache_key, "`.`",
+                    table->real_name, "`", NullS);
+      Query_log_event qinfo(thd, query, (ulong)(end-query), 0, FALSE);
+      /*
+        Imagine the thread had created a temp table, then was doing a SELECT, and
+        the SELECT was killed. Then it's not clever to mark the statement above as
+        "killed", because it's not really a statement updating data, and there
+        are 99.99% chances it will succeed on slave. And, if thread is
+        killed now, it's not clever either.
+        If a real update (one updating a persistent table) was killed on the
+        master, then this real update will be logged with error_code=killed,
+        rightfully causing the slave to stop.
+      */
+      qinfo.error_code= 0;
+      mysql_bin_log.write(&qinfo);
     }
     next=table->next;
     close_temporary(table);
   }
-  if (query && found_user_tables && mysql_bin_log.is_open())
-  {
-    /* The -1 is to remove last ',' */
-    thd->clear_error();
-    Query_log_event qinfo(thd, query, (ulong)(end-query)-1, 0, FALSE);
-    /*
-      Imagine the thread had created a temp table, then was doing a SELECT, and
-      the SELECT was killed. Then it's not clever to mark the statement above as
-      "killed", because it's not really a statement updating data, and there
-      are 99.99% chances it will succeed on slave.
-      If a real update (one updating a persistent table) was killed on the
-      master, then this real update will be logged with error_code=killed,
-      rightfully causing the slave to stop.
-    */
-    qinfo.error_code= 0;
-    mysql_bin_log.write(&qinfo);
-  }
   thd->temporary_tables=0;
 }