Fix of LP BUG#780386.

  
  ALL subquery should return TRUE if subquery rowa set is empty independently
  of left part.  The problem was that Item_func_(eq,ne,gt,ge,lt,le) do not
  call execution of second argument if first is NULL no in this case subquery
  will not be executed and when Item_func_not_all calls any_value() of the
  subquery or aggregation function which report that there was rows. So for
  NULL < ALL (SELECT...) result was FALSE instead of TRUE.
  
  Fix is just swapping of arguments of Item_func_(eq,ne,gt,ge,lt,le) (with
  changing the operation if it is needed) so that result will be the same
  (for examole a < b is equal to b > a). This fix exploit the fact that
  first argument will be executed in any case.

mysql-test/r/subselect.result

@@ -270,7 +270,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	3	100.00	
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>((`test`.`t3`.`a` >= (select min(`test`.`t2`.`b`) from `test`.`t2`)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>(((select min(`test`.`t2`.`b`) from `test`.`t2`) <= `test`.`t3`.`a`))
 select * from t3 where a >= all (select b from t2);
 a
 7
@@ -1532,7 +1532,7 @@ INSERT INTO t1 VALUES ('z','?');
 select * from t1 where s1 > (select max(s2) from t1);
 ERROR HY000: Illegal mix of collations (latin1_german1_ci,IMPLICIT) and (latin1_swedish_ci,IMPLICIT) for operation '>'
 select * from t1 where s1 > any (select max(s2) from t1);
-ERROR HY000: Illegal mix of collations (latin1_german1_ci,IMPLICIT) and (latin1_swedish_ci,IMPLICIT) for operation '>'
+ERROR HY000: Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (latin1_german1_ci,IMPLICIT) for operation '<'
 drop table t1;
 create table t1(toid int,rd int);
 create table t2(userid int,pmnew int,pmtotal int);
@@ -1621,7 +1621,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((`test`.`t3`.`a` < (select max(NULL) from `test`.`t2`)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>(((select max(NULL) from `test`.`t2`) > `test`.`t3`.`a`))
 select * from t3 where a >= some (select b from t2);
 a
 explain extended select * from t3 where a >= some (select b from t2);
@@ -1629,7 +1629,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>((`test`.`t3`.`a` >= (select min(NULL) from `test`.`t2`)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>(((select min(NULL) from `test`.`t2`) <= `test`.`t3`.`a`))
 select * from t3 where a >= all (select b from t2 group by 1);
 a
 6
@@ -1640,7 +1640,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((`test`.`t3`.`a` < <max>(select NULL from `test`.`t2` group by 1)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((<max>(select NULL from `test`.`t2` group by 1) > `test`.`t3`.`a`))
 select * from t3 where a >= some (select b from t2 group by 1);
 a
 explain extended select * from t3 where a >= some (select b from t2 group by 1);
@@ -1648,13 +1648,13 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>((`test`.`t3`.`a` >= <min>(select NULL from `test`.`t2` group by 1)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>((<min>(select NULL from `test`.`t2` group by 1) <= `test`.`t3`.`a`))
 select * from t3 where NULL >= any (select b from t2);
 a
 explain extended select * from t3 where NULL >= any (select b from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
-2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+2	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
 Warnings:
 Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where 0
 select * from t3 where NULL >= any (select b from t2 group by 1);
@@ -1662,7 +1662,7 @@ a
 explain extended select * from t3 where NULL >= any (select b from t2 group by 1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
-2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+2	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
 Warnings:
 Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where 0
 select * from t3 where NULL >= some (select b from t2);
@@ -1670,7 +1670,7 @@ a
 explain extended select * from t3 where NULL >= some (select b from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
-2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+2	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
 Warnings:
 Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where 0
 select * from t3 where NULL >= some (select b from t2 group by 1);
@@ -1678,7 +1678,7 @@ a
 explain extended select * from t3 where NULL >= some (select b from t2 group by 1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
-2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+2	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
 Warnings:
 Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where 0
 insert into t2 values (2,2), (2,1), (3,3), (3,1);
@@ -1691,7 +1691,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	4	100.00	Using temporary; Using filesort
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((`test`.`t3`.`a` <= <max>(select max(`test`.`t2`.`b`) from `test`.`t2` group by `test`.`t2`.`a`)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((<max>(select max(`test`.`t2`.`b`) from `test`.`t2` group by `test`.`t2`.`a`) >= `test`.`t3`.`a`))
 drop table t2, t3;
 CREATE TABLE `t1` ( `id` mediumint(9) NOT NULL auto_increment, `taskid` bigint(20) NOT NULL default '0', `dbid` int(11) NOT NULL default '0', `create_date` datetime NOT NULL default '0000-00-00 00:00:00', `last_update` datetime NOT NULL default '0000-00-00 00:00:00', PRIMARY KEY  (`id`)) ENGINE=MyISAM CHARSET=latin1 AUTO_INCREMENT=3 ;
 INSERT INTO `t1` (`id`, `taskid`, `dbid`, `create_date`,`last_update`) VALUES (1, 1, 15, '2003-09-29 10:31:36', '2003-09-29 10:31:36'), (2, 1, 21, now(), now());
@@ -5045,4 +5045,23 @@ a
 SELECT a FROM t1 WHERE b <> ALL ( SELECT b FROM t1 GROUP BY b );
 a
 drop table t1;
+#
+# Fix of LP BUG#780386 (NULL left part with empty ALL subquery).
+#
+CREATE TABLE t1 ( f11 int) ;
+INSERT IGNORE INTO t1 VALUES (0),(0);
+CREATE TABLE t2 ( f3 int, f10 int, KEY (f10,f3)) ;
+INSERT IGNORE INTO t2 VALUES (NULL,NULL),(5,0);
+DROP TABLE IF EXISTS t3;
+Warnings:
+Note	1051	Unknown table 't3'
+CREATE TABLE t3 ( f3 int) ;
+INSERT INTO t3 VALUES (0),(0);
+SELECT a1.f3 AS r FROM t2 AS a1 , t1 WHERE a1.f3 < ALL ( SELECT f3 FROM t3 WHERE f3 = 1 ) ;
+r
+NULL
+5
+NULL
+5
+DROP TABLE t1, t2, t3;
 End of 5.2 tests

mysql-test/suite/pbxt/r/subselect.result

@@ -270,7 +270,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	3	100.00	
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>((`test`.`t3`.`a` >= (select min(`test`.`t2`.`b`) from `test`.`t2`)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>(((select min(`test`.`t2`.`b`) from `test`.`t2`) <= `test`.`t3`.`a`))
 select * from t3 where a >= all (select b from t2);
 a
 7
@@ -1407,7 +1407,7 @@ INSERT INTO t1 VALUES ('z','?');
 select * from t1 where s1 > (select max(s2) from t1);
 ERROR HY000: Illegal mix of collations (latin1_german1_ci,IMPLICIT) and (latin1_swedish_ci,IMPLICIT) for operation '>'
 select * from t1 where s1 > any (select max(s2) from t1);
-ERROR HY000: Illegal mix of collations (latin1_german1_ci,IMPLICIT) and (latin1_swedish_ci,IMPLICIT) for operation '>'
+ERROR HY000: Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (latin1_german1_ci,IMPLICIT) for operation '<'
 drop table t1;
 create table t1(toid int,rd int);
 create table t2(userid int,pmnew int,pmtotal int);
@@ -1496,7 +1496,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	0	0.00	
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((`test`.`t3`.`a` < (select max(`test`.`t2`.`b`) from `test`.`t2`)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>(((select max(`test`.`t2`.`b`) from `test`.`t2`) > `test`.`t3`.`a`))
 select * from t3 where a >= some (select b from t2);
 a
 explain extended select * from t3 where a >= some (select b from t2);
@@ -1504,7 +1504,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	0	0.00	
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>((`test`.`t3`.`a` >= (select min(`test`.`t2`.`b`) from `test`.`t2`)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>(((select min(`test`.`t2`.`b`) from `test`.`t2`) <= `test`.`t3`.`a`))
 select * from t3 where a >= all (select b from t2 group by 1);
 a
 6
@@ -1515,7 +1515,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	0	0.00	Using temporary; Using filesort
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((`test`.`t3`.`a` < <max>(select `test`.`t2`.`b` from `test`.`t2` group by 1)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((<max>(select `test`.`t2`.`b` from `test`.`t2` group by 1) > `test`.`t3`.`a`))
 select * from t3 where a >= some (select b from t2 group by 1);
 a
 explain extended select * from t3 where a >= some (select b from t2 group by 1);
@@ -1523,7 +1523,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	0	0.00	Using temporary; Using filesort
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>((`test`.`t3`.`a` >= <min>(select `test`.`t2`.`b` from `test`.`t2` group by 1)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <nop>((<min>(select `test`.`t2`.`b` from `test`.`t2` group by 1) <= `test`.`t3`.`a`))
 select * from t3 where NULL >= any (select b from t2);
 a
 explain extended select * from t3 where NULL >= any (select b from t2);
@@ -1566,7 +1566,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	4	100.00	Using temporary; Using filesort
 Warnings:
-Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((`test`.`t3`.`a` <= <max>(select max(`test`.`t2`.`b`) from `test`.`t2` group by `test`.`t2`.`a`)))
+Note	1003	select `test`.`t3`.`a` AS `a` from `test`.`t3` where <not>((<max>(select max(`test`.`t2`.`b`) from `test`.`t2` group by `test`.`t2`.`a`) >= `test`.`t3`.`a`))
 drop table t2, t3;
 CREATE TABLE `t1` ( `id` mediumint(9) NOT NULL auto_increment, `taskid` bigint(20) NOT NULL default '0', `dbid` int(11) NOT NULL default '0', `create_date` datetime NOT NULL default '0000-00-00 00:00:00', `last_update` datetime NOT NULL default '0000-00-00 00:00:00', PRIMARY KEY  (`id`)) ENGINE=MyISAM CHARSET=latin1 AUTO_INCREMENT=3 ;
 INSERT INTO `t1` (`id`, `taskid`, `dbid`, `create_date`,`last_update`) VALUES (1, 1, 15, '2003-09-29 10:31:36', '2003-09-29 10:31:36'), (2, 1, 21, now(), now());

mysql-test/t/subselect.test

@@ -3909,4 +3909,20 @@ SELECT a FROM t1 WHERE b <> ALL ( SELECT b FROM t1 GROUP BY b );
 
 drop table t1;
 
+--echo #
+--echo # Fix of LP BUG#780386 (NULL left part with empty ALL subquery).
+--echo #
+CREATE TABLE t1 ( f11 int) ;
+INSERT IGNORE INTO t1 VALUES (0),(0);
+
+CREATE TABLE t2 ( f3 int, f10 int, KEY (f10,f3)) ;
+INSERT IGNORE INTO t2 VALUES (NULL,NULL),(5,0);
+
+DROP TABLE IF EXISTS t3;
+CREATE TABLE t3 ( f3 int) ;
+INSERT INTO t3 VALUES (0),(0);
+
+SELECT a1.f3 AS r FROM t2 AS a1 , t1 WHERE a1.f3 < ALL ( SELECT f3 FROM t3 WHERE f3 = 1 ) ;
+DROP TABLE t1, t2, t3;
+
 --echo End of 5.2 tests

sql/item_cmpfunc.cc

@@ -245,36 +245,61 @@ Item_bool_func2* Eq_creator::create(Item *a, Item *b) const
   return new Item_func_eq(a, b);
 }
 
+Item_bool_func2* Eq_creator::create_swap(Item *a, Item *b) const
+{
+  return new Item_func_eq(b, a);
+}
 
 Item_bool_func2* Ne_creator::create(Item *a, Item *b) const
 {
   return new Item_func_ne(a, b);
 }
 
+Item_bool_func2* Ne_creator::create_swap(Item *a, Item *b) const
+{
+  return new Item_func_ne(b, a);
+}
 
 Item_bool_func2* Gt_creator::create(Item *a, Item *b) const
 {
   return new Item_func_gt(a, b);
 }
 
+Item_bool_func2* Gt_creator::create_swap(Item *a, Item *b) const
+{
+  return new Item_func_lt(b, a);
+}
 
 Item_bool_func2* Lt_creator::create(Item *a, Item *b) const
 {
   return new Item_func_lt(a, b);
 }
 
+Item_bool_func2* Lt_creator::create_swap(Item *a, Item *b) const
+{
+  return new Item_func_gt(b, a);
+}
 
 Item_bool_func2* Ge_creator::create(Item *a, Item *b) const
 {
   return new Item_func_ge(a, b);
 }
 
+Item_bool_func2* Ge_creator::create_swap(Item *a, Item *b) const
+{
+  return new Item_func_le(b, a);
+}
 
 Item_bool_func2* Le_creator::create(Item *a, Item *b) const
 {
   return new Item_func_le(a, b);
 }
 
+Item_bool_func2* Le_creator::create_swap(Item *a, Item *b) const
+{
+  return new Item_func_ge(b, a);
+}
+
 /*
   Test functions
   Most of these  returns 0LL if false and 1LL if true and

sql/item_cmpfunc.h

@@ -270,7 +270,14 @@ class Comp_creator
 public:
   Comp_creator() {}                           /* Remove gcc warning */
   virtual ~Comp_creator() {}                  /* Remove gcc warning */
+  /**
+    Create operation with given arguments.
+  */
   virtual Item_bool_func2* create(Item *a, Item *b) const = 0;
+  /**
+    Create operation with given arguments in swap order.
+  */
+  virtual Item_bool_func2* create_swap(Item *a, Item *b) const = 0;
   virtual const char* symbol(bool invert) const = 0;
   virtual bool eqne_op() const = 0;
   virtual bool l_op() const = 0;
@@ -282,6 +289,7 @@ public:
   Eq_creator() {}                             /* Remove gcc warning */
   virtual ~Eq_creator() {}                    /* Remove gcc warning */
   virtual Item_bool_func2* create(Item *a, Item *b) const;
+  virtual Item_bool_func2* create_swap(Item *a, Item *b) const;
   virtual const char* symbol(bool invert) const { return invert? "<>" : "="; }
   virtual bool eqne_op() const { return 1; }
   virtual bool l_op() const { return 0; }
@@ -293,6 +301,7 @@ public:
   Ne_creator() {}                             /* Remove gcc warning */
   virtual ~Ne_creator() {}                    /* Remove gcc warning */
   virtual Item_bool_func2* create(Item *a, Item *b) const;
+  virtual Item_bool_func2* create_swap(Item *a, Item *b) const;
   virtual const char* symbol(bool invert) const { return invert? "=" : "<>"; }
   virtual bool eqne_op() const { return 1; }
   virtual bool l_op() const { return 0; }
@@ -304,6 +313,7 @@ public:
   Gt_creator() {}                             /* Remove gcc warning */
   virtual ~Gt_creator() {}                    /* Remove gcc warning */
   virtual Item_bool_func2* create(Item *a, Item *b) const;
+  virtual Item_bool_func2* create_swap(Item *a, Item *b) const;
   virtual const char* symbol(bool invert) const { return invert? "<=" : ">"; }
   virtual bool eqne_op() const { return 0; }
   virtual bool l_op() const { return 0; }
@@ -315,6 +325,7 @@ public:
   Lt_creator() {}                             /* Remove gcc warning */
   virtual ~Lt_creator() {}                    /* Remove gcc warning */
   virtual Item_bool_func2* create(Item *a, Item *b) const;
+  virtual Item_bool_func2* create_swap(Item *a, Item *b) const;
   virtual const char* symbol(bool invert) const { return invert? ">=" : "<"; }
   virtual bool eqne_op() const { return 0; }
   virtual bool l_op() const { return 1; }
@@ -326,6 +337,7 @@ public:
   Ge_creator() {}                             /* Remove gcc warning */
   virtual ~Ge_creator() {}                    /* Remove gcc warning */
   virtual Item_bool_func2* create(Item *a, Item *b) const;
+  virtual Item_bool_func2* create_swap(Item *a, Item *b) const;
   virtual const char* symbol(bool invert) const { return invert? "<" : ">="; }
   virtual bool eqne_op() const { return 0; }
   virtual bool l_op() const { return 0; }
@@ -337,6 +349,7 @@ public:
   Le_creator() {}                             /* Remove gcc warning */
   virtual ~Le_creator() {}                    /* Remove gcc warning */
   virtual Item_bool_func2* create(Item *a, Item *b) const;
+  virtual Item_bool_func2* create_swap(Item *a, Item *b) const;
   virtual const char* symbol(bool invert) const { return invert? ">" : "<="; }
   virtual bool eqne_op() const { return 0; }
   virtual bool l_op() const { return 1; }

sql/item_subselect.cc

@@ -1076,8 +1076,11 @@ Item_in_subselect::single_value_transformer(JOIN *join,
       if (upper_item)
         upper_item->set_sub_test(item);
     }
-    /* fix fields is already called for  left expression */
-    substitution= func->create(left_expr, subs);
+    /*
+      The swap is needed for expressions of type 'f1 < ALL ( SELECT ....)'
+      where we want to evaluate the sub query even if f1 would be null.
+    */
+    substitution= func->create_swap(left_expr, subs);
     DBUG_RETURN(RES_OK);
   }