Merge bk-internal:/home/bk/mysql-5.0-opt

into  macbook.gmz:/Users/kgeorge/mysql/work/B21798-5.0-opt-merge

mysql-test/r/subselect.result

@@ -3458,6 +3458,32 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 4	UNION	t12	system	NULL	NULL	NULL	NULL	0	const row not found
 NULL	UNION RESULT	<union2,4>	ALL	NULL	NULL	NULL	NULL	NULL	
 DROP TABLE t1;
+CREATE TABLE t1 (a VARCHAR(250), b INT auto_increment, PRIMARY KEY (b));
+insert into t1 (a) values (FLOOR(rand() * 100));
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+SELECT a, 
+(SELECT REPEAT(' ',250) FROM t1 i1 
+WHERE i1.b=t1.a ORDER BY RAND() LIMIT 1) AS a 
+FROM t1 ORDER BY a LIMIT 5;
+a	a
+0	NULL
+0	NULL
+0	NULL
+0	NULL
+0	NULL
+DROP TABLE t1;
 CREATE TABLE t1 (a INT, b INT);
 CREATE TABLE t2 (a INT);
 INSERT INTO t2 values (1);

mysql-test/t/subselect.test

@@ -2370,6 +2370,32 @@ explain select * from t1 where not exists
 
 DROP TABLE t1;
 
+#
+# Bug#21798: memory leak during query execution with subquery in column 
+#             list using a function
+#
+CREATE TABLE t1 (a VARCHAR(250), b INT auto_increment, PRIMARY KEY (b));
+insert into t1 (a) values (FLOOR(rand() * 100));
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+insert into t1 (a) select FLOOR(rand() * 100) from t1;
+
+SELECT a, 
+       (SELECT REPEAT(' ',250) FROM t1 i1 
+        WHERE i1.b=t1.a ORDER BY RAND() LIMIT 1) AS a 
+FROM t1 ORDER BY a LIMIT 5;
+DROP TABLE t1;
+
 #
 # Bug #21540: Subqueries with no from and aggregate functions return 
 #              wrong results

sql/mysql_priv.h

@@ -714,7 +714,8 @@ bool mysql_xa_recover(THD *thd);
 
 bool check_simple_select();
 
-SORT_FIELD * make_unireg_sortorder(ORDER *order, uint *length);
+SORT_FIELD * make_unireg_sortorder(ORDER *order, uint *length,
+                                  SORT_FIELD *sortorder);
 int setup_order(THD *thd, Item **ref_pointer_array, TABLE_LIST *tables,
 		List<Item> &fields, List <Item> &all_fields, ORDER *order);
 int setup_group(THD *thd, Item **ref_pointer_array, TABLE_LIST *tables,

sql/sql_delete.cc

@@ -167,7 +167,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds,
                                                    MYF(MY_FAE | MY_ZEROFILL));
     
       if (!(sortorder= make_unireg_sortorder((ORDER*) order->first,
-                                             &length)) ||
+                                             &length, NULL)) ||
 	  (table->sort.found_records = filesort(thd, table, sortorder, length,
                                                 select, HA_POS_ERROR,
                                                 &examined_rows))

sql/sql_select.cc

@@ -1575,6 +1575,7 @@ JOIN::exec()
 	{
 	  DBUG_VOID_RETURN;
 	}
+        sortorder= curr_join->sortorder;
       }
       
       thd->proc_info="Copying to group table";
@@ -1784,6 +1785,7 @@ JOIN::exec()
 			    (select_options & OPTION_FOUND_ROWS ?
 			     HA_POS_ERROR : unit->select_limit_cnt)))
 	DBUG_VOID_RETURN;
+      sortorder= curr_join->sortorder;
     }
   }
   /* XXX: When can we have here thd->net.report_error not zero? */
@@ -4950,9 +4952,28 @@ make_simple_join(JOIN *join,TABLE *tmp_table)
   JOIN_TAB *join_tab;
   DBUG_ENTER("make_simple_join");
 
-  if (!(tableptr=(TABLE**) join->thd->alloc(sizeof(TABLE*))) ||
-      !(join_tab=(JOIN_TAB*) join->thd->alloc(sizeof(JOIN_TAB))))
-    DBUG_RETURN(TRUE);
+  /*
+    Reuse TABLE * and JOIN_TAB if already allocated by a previous call
+    to this function through JOIN::exec (may happen for sub-queries).
+  */
+  if (!join->table_cache)
+  {
+    if (!(join->table_cache= (TABLE**) join->thd->alloc(sizeof(TABLE*))))
+      DBUG_RETURN(TRUE);                        /* purecov: inspected */
+    if (join->tmp_join)
+      join->tmp_join->table_cache= join->table_cache;
+  }
+  if (!join->join_tab_cache)
+  {
+    if (!(join->join_tab_cache=
+          (JOIN_TAB*) join->thd->alloc(sizeof(JOIN_TAB))))
+      DBUG_RETURN(TRUE);                        /* purecov: inspected */
+    if (join->tmp_join)
+      join->tmp_join->join_tab_cache= join->join_tab_cache;
+  }
+  tableptr= join->table_cache;
+  join_tab= join->join_tab_cache;
+
   join->join_tab=join_tab;
   join->table=tableptr; tableptr[0]=tmp_table;
   join->tables=1;
@@ -11982,7 +12003,6 @@ static int
 create_sort_index(THD *thd, JOIN *join, ORDER *order,
 		  ha_rows filesort_limit, ha_rows select_limit)
 {
-  SORT_FIELD *sortorder;
   uint length;
   ha_rows examined_rows;
   TABLE *table;
@@ -12004,7 +12024,8 @@ create_sort_index(THD *thd, JOIN *join, ORDER *order,
        !(join->select_options & SELECT_BIG_RESULT)) &&
       test_if_skip_sort_order(tab,order,select_limit,0))
     DBUG_RETURN(0);
-  if (!(sortorder=make_unireg_sortorder(order,&length)))
+  if (!(join->sortorder= 
+        make_unireg_sortorder(order,&length,join->sortorder)))
     goto err;				/* purecov: inspected */
 
   table->sort.io_cache=(IO_CACHE*) my_malloc(sizeof(IO_CACHE),
@@ -12051,7 +12072,7 @@ create_sort_index(THD *thd, JOIN *join, ORDER *order,
 
   if (table->s->tmp_table)
     table->file->info(HA_STATUS_VARIABLE);	// Get record count
-  table->sort.found_records=filesort(thd, table,sortorder, length,
+  table->sort.found_records=filesort(thd, table,join->sortorder, length,
                                      select, filesort_limit, &examined_rows);
   tab->records= table->sort.found_records;	// For SQL_CALC_ROWS
   if (select)
@@ -12398,7 +12419,8 @@ err:
 }
 
 
-SORT_FIELD *make_unireg_sortorder(ORDER *order, uint *length)
+SORT_FIELD *make_unireg_sortorder(ORDER *order, uint *length,
+                                  SORT_FIELD *sortorder)
 {
   uint count;
   SORT_FIELD *sort,*pos;
@@ -12407,7 +12429,9 @@ SORT_FIELD *make_unireg_sortorder(ORDER *order, uint *length)
   count=0;
   for (ORDER *tmp = order; tmp; tmp=tmp->next)
     count++;
-  pos=sort=(SORT_FIELD*) sql_alloc(sizeof(SORT_FIELD)*(count+1));
+  if (!sortorder)
+    sortorder= (SORT_FIELD*) sql_alloc(sizeof(SORT_FIELD)*(count+1));
+  pos=sort=sortorder;
   if (!pos)
     return 0;
 

sql/sql_select.h

@@ -282,6 +282,18 @@ public:
   bool union_part; // this subselect is part of union 
   bool optimized; // flag to avoid double optimization in EXPLAIN
 
+  /* 
+    storage for caching buffers allocated during query execution. 
+    These buffers allocations need to be cached as the thread memory pool is
+    cleared only at the end of the execution of the whole query and not caching
+    allocations that occur in repetition at execution time will result in 
+    excessive memory usage.
+  */  
+  SORT_FIELD *sortorder;                        // make_unireg_sortorder()
+  TABLE **table_cache;                          // make_simple_join()
+  JOIN_TAB *join_tab_cache;                     // make_simple_join()
+  /* end of allocation caching storage */
+
   JOIN(THD *thd_arg, List<Item> &fields_arg, ulonglong select_options_arg,
        select_result *result_arg)
     :fields_list(fields_arg)
@@ -307,6 +319,9 @@ public:
     examined_rows= 0;
     exec_tmp_table1= 0;
     exec_tmp_table2= 0;
+    sortorder= 0;
+    table_cache= 0;
+    join_tab_cache= 0;
     thd= thd_arg;
     sum_funcs= sum_funcs2= 0;
     procedure= 0;

sql/sql_table.cc

@@ -4095,7 +4095,7 @@ copy_data_between_tables(TABLE *from,TABLE *to,
     if (thd->lex->select_lex.setup_ref_array(thd, order_num) ||
 	setup_order(thd, thd->lex->select_lex.ref_pointer_array,
 		    &tables, fields, all_fields, order) ||
-	!(sortorder=make_unireg_sortorder(order, &length)) ||
+	!(sortorder=make_unireg_sortorder(order, &length, NULL)) ||
 	(from->sort.found_records = filesort(thd, from, sortorder, length,
 					     (SQL_SELECT *) 0, HA_POS_ERROR,
 					     &examined_rows)) ==

sql/sql_update.cc

@@ -311,7 +311,7 @@ int mysql_update(THD *thd,
 
       table->sort.io_cache = (IO_CACHE *) my_malloc(sizeof(IO_CACHE),
 						    MYF(MY_FAE | MY_ZEROFILL));
-      if (!(sortorder=make_unireg_sortorder(order, &length)) ||
+      if (!(sortorder=make_unireg_sortorder(order, &length, NULL)) ||
           (table->sort.found_records = filesort(thd, table, sortorder, length,
 						select, limit,
 						&examined_rows))