Merge gkodinov@bk-internal.mysql.com:/home/bk/mysql-5.0-opt

into  rakia.(none):/home/kgeorge/mysql/autopush/B21019-5.0-opt

mysql-test/r/subselect2.result

@@ -132,3 +132,15 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 5	DEPENDENT SUBQUERY	t3	unique_subquery	PRIMARY,FFOLDERID_IDX	PRIMARY	34	func	1	Using index; Using where
 6	DEPENDENT SUBQUERY	t3	unique_subquery	PRIMARY,FFOLDERID_IDX,CMFLDRPARNT_IDX	PRIMARY	34	func	1	Using index; Using where
 drop table t1, t2, t3, t4;
+CREATE TABLE t1 (a int(10) , PRIMARY KEY (a)) Engine=InnoDB;
+INSERT INTO t1 VALUES (1),(2);
+CREATE TABLE t2 (a int(10), PRIMARY KEY (a)) Engine=InnoDB;
+INSERT INTO t2 VALUES (1);
+CREATE TABLE t3 (a int(10), b int(10), c int(10),
+PRIMARY KEY (a)) Engine=InnoDB;
+INSERT INTO t3 VALUES (1,2,1);
+SELECT t1.* FROM t1 WHERE (SELECT COUNT(*) FROM t3,t2 WHERE t3.c=t2.a 
+and t2.a='1' AND t1.a=t3.b) > 0;
+a
+2
+DROP TABLE t1,t2,t3;

mysql-test/t/subselect2.test

@@ -150,3 +150,21 @@ EXPLAIN SELECT t2.*, t4.DOCTYPENAME, t1.CONTENTSIZE,t1.MIMETYPE FROM t2 INNER JO
 
 drop table t1, t2, t3, t4;
 # End of 4.1 tests
+
+#
+# Bug #20792: Incorrect results from aggregate subquery
+#
+CREATE TABLE t1 (a int(10) , PRIMARY KEY (a)) Engine=InnoDB;
+INSERT INTO t1 VALUES (1),(2);
+
+CREATE TABLE t2 (a int(10), PRIMARY KEY (a)) Engine=InnoDB;
+INSERT INTO t2 VALUES (1);
+
+CREATE TABLE t3 (a int(10), b int(10), c int(10),
+                PRIMARY KEY (a)) Engine=InnoDB;
+INSERT INTO t3 VALUES (1,2,1);
+
+SELECT t1.* FROM t1 WHERE (SELECT COUNT(*) FROM t3,t2 WHERE t3.c=t2.a 
+                           and t2.a='1' AND t1.a=t3.b) > 0;
+
+DROP TABLE t1,t2,t3;

sql/item.h

@@ -752,7 +752,7 @@ class Item {
   virtual bool find_item_in_field_list_processor(byte *arg) { return 0; }
   virtual bool change_context_processor(byte *context) { return 0; }
   virtual bool reset_query_id_processor(byte *query_id) { return 0; }
-  virtual bool func_type_checker_processor(byte *arg) { return 0; }
+  virtual bool is_expensive_processor(byte *arg) { return 0; }
 
   virtual Item *equal_fields_propagator(byte * arg) { return this; }
   virtual Item *set_no_const_sub(byte *arg) { return this; }

sql/item_func.cc

@@ -399,9 +399,9 @@ Field *Item_func::tmp_table_field(TABLE *t_arg)
 }
 
 
-bool Item_func::func_type_checker_processor(byte *arg)
+bool Item_func::is_expensive_processor(byte *arg)
 {
-  return *((Functype*)arg) == functype();
+  return is_expensive();
 }
 
 

sql/item_func.h

@@ -189,7 +189,8 @@ class Item_func :public Item_result_field
   Item *transform(Item_transformer transformer, byte *arg);
   void traverse_cond(Cond_traverser traverser,
                      void * arg, traverse_order order);
-  bool func_type_checker_processor(byte *arg);
+  bool is_expensive_processor(byte *arg);
+  virtual bool is_expensive() { return 0; }
 };
 
 
@@ -947,6 +948,7 @@ class Item_udf_func :public Item_func
   void cleanup();
   Item_result result_type () const { return udf.result_type(); }
   table_map not_null_tables() const { return 0; }
+  bool is_expensive() { return 1; }
 };
 
 
@@ -1475,6 +1477,7 @@ class Item_func_sp :public Item_func
   virtual enum Functype functype() const { return FUNC_SP; }
 
   bool fix_fields(THD *thd, Item **ref);
+  bool is_expensive() { return 1; }
 };
 
 

sql/sql_select.cc

@@ -1073,10 +1073,7 @@ JOIN::optimize()
       for (ORDER *tmp_order= order; tmp_order ; tmp_order=tmp_order->next)
       {
         Item *item= *tmp_order->item;
-        Item_func::Functype type=Item_func::FUNC_SP;
-        Item_func::Functype type1=Item_func::UDF_FUNC;
-        if (item->walk(&Item::func_type_checker_processor,(byte*)&type) ||
-            item->walk(&Item::func_type_checker_processor,(byte*)&type1))
+        if (item->walk(&Item::is_expensive_processor,(byte*)0))
         {
           /* Force tmp table without sort */
           need_tmp=1; simple_order=simple_group=0;
@@ -6197,10 +6194,16 @@ return_zero_rows(JOIN *join, select_result *result,TABLE_LIST *tables,
   DBUG_RETURN(0);
 }
 
-
+/*
+  used only in JOIN::clear
+*/
 static void clear_tables(JOIN *join)
 {
-  for (uint i=0 ; i < join->tables ; i++)
+  /* 
+    must clear only the non-const tables, as const tables
+    are not re-calculated.
+  */
+  for (uint i=join->const_tables ; i < join->tables ; i++)
     mark_as_null_row(join->table[i]);		// All fields are NULL
 }