Merge magare.gmz:/home/kgeorge/mysql/work/B32036-5.0-opt

into  magare.gmz:/home/kgeorge/mysql/work/B32036-5.1-opt


mysql-test/r/subselect.result:
  merged fix for bug 32036 to 5.1-opt
mysql-test/t/subselect.test:
  merged fix for bug 32036 to 5.1-opt
sql/sql_yacc.yy:
  merged fix for bug 32036 to 5.1-opt

mysql-test/r/subselect.result

@@ -3558,22 +3558,19 @@ SELECT sql_no_cache * FROM t1 WHERE NOT EXISTS
 (SELECT i FROM t1) UNION 
 (SELECT i FROM t1)
 );
-i
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNION 
+(SELECT i FROM t1)
+)' at line 3
 SELECT * FROM t1 
 WHERE NOT EXISTS (((SELECT i FROM t1) UNION (SELECT i FROM t1)));
-i
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNION (SELECT i FROM t1)))' at line 2
 explain select ((select t11.i from t1 t11) union (select t12.i from t1 t12))
 from t1;
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'union (select t12.i from t1 t12))
 from t1' at line 1
 explain select * from t1 where not exists 
 ((select t11.i from t1 t11) union (select t12.i from t1 t12));
-id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	0	const row not found
-2	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
-3	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
-4	UNION	t12	system	NULL	NULL	NULL	NULL	0	const row not found
-NULL	UNION RESULT	<union2,4>	ALL	NULL	NULL	NULL	NULL	NULL	
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'union (select t12.i from t1 t12))' at line 2
 DROP TABLE t1;
 CREATE TABLE t1 (a VARCHAR(250), b INT auto_increment, PRIMARY KEY (b));
 insert into t1 (a) values (FLOOR(rand() * 100));
@@ -4331,6 +4328,28 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1 WHERE LENGTH(a)<500);
 a	b
 DROP TABLE t1,t2;
+CREATE TABLE t1 (a INT);
+CREATE TABLE t2 (a INT);
+INSERT INTO t1 VALUES (1),(2);
+INSERT INTO t2 VALUES (1),(2);
+SELECT 2 FROM t1 WHERE EXISTS ((SELECT 1 FROM t2 WHERE t1.a=t2.a));
+2
+2
+2
+EXPLAIN EXTENDED
+SELECT 2 FROM t1 WHERE EXISTS ((SELECT 1 FROM t2 WHERE t1.a=t2.a));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+2	DEPENDENT SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
+Warnings:
+Note	1276	Field or reference 'test.t1.a' of SELECT #2 was resolved in SELECT #1
+Note	1003	select 2 AS `2` from `test`.`t1` where exists(select 1 AS `1` from `test`.`t2` where (`test`.`t1`.`a` = `test`.`t2`.`a`))
+EXPLAIN EXTENDED
+SELECT 2 FROM t1 WHERE EXISTS ((SELECT 1 FROM t2 WHERE t1.a=t2.a) UNION 
+(SELECT 1 FROM t2 WHERE t1.a = t2.a));
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNION 
+(SELECT 1 FROM t2 WHERE t1.a = t2.a))' at line 2
+DROP TABLE t1,t2;
 End of 5.0 tests.
 CREATE TABLE t1 (a int, b int);
 INSERT INTO t1 VALUES (2,22),(1,11),(2,22);

mysql-test/t/subselect.test

@@ -2455,12 +2455,16 @@ DROP TABLE t1, t2;
 CREATE TABLE t1 (i INT);
 
 (SELECT i FROM t1) UNION (SELECT i FROM t1);
+#TODO:not supported
+--error ER_PARSE_ERROR
 SELECT sql_no_cache * FROM t1 WHERE NOT EXISTS 
   (
    (SELECT i FROM t1) UNION 
    (SELECT i FROM t1)
   );
 
+#TODO:not supported
+--error ER_PARSE_ERROR
 SELECT * FROM t1 
 WHERE NOT EXISTS (((SELECT i FROM t1) UNION (SELECT i FROM t1)));
 
@@ -2468,7 +2472,9 @@ WHERE NOT EXISTS (((SELECT i FROM t1) UNION (SELECT i FROM t1)));
 --error 1064
 explain select ((select t11.i from t1 t11) union (select t12.i from t1 t12))
   from t1;
-#supported
+
+#TODO:not supported
+--error ER_PARSE_ERROR
 explain select * from t1 where not exists 
   ((select t11.i from t1 t11) union (select t12.i from t1 t12));
 
@@ -3201,6 +3207,30 @@ GROUP BY a;
 DROP TABLE t1;
 
 
+#
+# Bug #32036: EXISTS within a WHERE clause with a UNION crashes MySQL 5.122
+#
+
+CREATE TABLE t1 (a INT);
+CREATE TABLE t2 (a INT);
+
+INSERT INTO t1 VALUES (1),(2);
+INSERT INTO t2 VALUES (1),(2);
+
+SELECT 2 FROM t1 WHERE EXISTS ((SELECT 1 FROM t2 WHERE t1.a=t2.a));
+EXPLAIN EXTENDED
+SELECT 2 FROM t1 WHERE EXISTS ((SELECT 1 FROM t2 WHERE t1.a=t2.a));
+
+
+#TODO:not supported
+--error ER_PARSE_ERROR
+EXPLAIN EXTENDED
+SELECT 2 FROM t1 WHERE EXISTS ((SELECT 1 FROM t2 WHERE t1.a=t2.a) UNION 
+                               (SELECT 1 FROM t2 WHERE t1.a = t2.a));
+
+DROP TABLE t1,t2;
+
+
 --echo End of 5.0 tests.
 
 #

sql/sql_yacc.yy

@@ -1228,7 +1228,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
 
 %type <variable> internal_variable_name
 
-%type <select_lex> subselect subselect_init
+%type <select_lex> subselect take_first_select
         get_select_lex
 
 %type <boolfunc2creator> comp_op
@@ -11644,37 +11644,22 @@ union_option:
         | ALL       { $$=0; }
         ;
 
-subselect:
-          SELECT_SYM subselect_start subselect_init subselect_end
-          {
-            $$= $3;
-          }
-        | '(' subselect_start subselect ')'
-          {
-            THD *thd= YYTHD;
-            /*
-              note that a local variable can't be used for
-              $3 as it's used in local variable construction
-              and some compilers can't guarnatee the order
-              in which the local variables are initialized.
-            */
-            List_iterator<Item> it($3->item_list);
-            Item *item;
-            /*
-              we must fill the items list for the "derived table".
-            */
-            while ((item= it++))
-              add_item_to_list(thd, item);
-          }
-          union_clause subselect_end { $$= $3; }
-        ;
+take_first_select: /* empty */
+        {
+          $$= Lex->current_select->master_unit()->first_select();
+        };
 
-subselect_init:
-          select_init2
-          {
-            $$= Lex->current_select->master_unit()->first_select();
-          }
-        ;
+subselect:
+        SELECT_SYM subselect_start select_init2 take_first_select 
+        subselect_end
+        {
+          $$= $4;
+        }
+        | '(' subselect_start select_paren take_first_select 
+        subselect_end ')'
+        {
+          $$= $4;
+        };
 
 subselect_start:
           {