manual merge 5.0-bugteam --> 5.1-bugteam

mysql-test/r/select.result

@@ -4373,6 +4373,19 @@ f3	f4	count
 1	abc	1
 1	def	2
 drop table t1, t2, t3;
+CREATE TABLE t1 (a INT KEY, b INT);
+INSERT INTO t1 VALUES (1,1), (2,2), (3,3), (4,4);
+EXPLAIN EXTENDED SELECT a, b FROM t1 WHERE a > 1 AND a = b LIMIT 2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	4	NULL	3	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where ((`test`.`t1`.`b` = `test`.`t1`.`a`) and (`test`.`t1`.`a` > 1)) limit 2
+EXPLAIN EXTENDED SELECT a, b FROM t1 WHERE a > 1 AND b = a LIMIT 2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	4	NULL	3	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where ((`test`.`t1`.`a` = `test`.`t1`.`b`) and (`test`.`t1`.`a` > 1)) limit 2
+DROP TABLE t1;
 End of 5.0 tests
 create table t1(a INT, KEY (a));
 INSERT INTO t1 VALUES (1),(2),(3),(4),(5);

mysql-test/t/select.test

@@ -3726,6 +3726,20 @@ cr.f4 = cr2.f4
 GROUP BY a.f3, cr.f4;
 
 drop table t1, t2, t3;
+
+
+#
+# Bug #40925: Equality propagation takes non indexed attribute
+#
+
+CREATE TABLE t1 (a INT KEY, b INT);
+INSERT INTO t1 VALUES (1,1), (2,2), (3,3), (4,4);
+
+EXPLAIN EXTENDED SELECT a, b FROM t1 WHERE a > 1 AND a = b LIMIT 2;
+EXPLAIN EXTENDED SELECT a, b FROM t1 WHERE a > 1 AND b = a LIMIT 2;
+
+DROP TABLE t1;
+ 
 --echo End of 5.0 tests
 
 #

sql/item.cc

@@ -4468,7 +4468,7 @@ Item *Item_field::replace_equal_field(uchar *arg)
       return const_item;
     }
     Item_field *subst= item_equal->get_first();
-    if (subst && !field->eq(subst->field))
+    if (subst && field->table != subst->field->table && !field->eq(subst->field))
       return subst;
   }
   return this;