database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-29 05:21:33 +03:00
Code Activity

Bug #32036: EXISTS within a WHERE clause with a UNION

Browse Source 
crashes MySQL 5.122
There was a difference in how UNIONs are handled
on top level and when in sub-query.
Because the rules for sub-queries were syntactically
allowing cases that are not currently supported by
the server we had crashes (this bug) or wrong results
(bug 32051).
Fixed by making the syntax rules for UNIONs match the 
ones at top level.

These rules however do not support nesting UNIONs, e.g.
(SELECT a FROM t1 UNION ALL SELECT b FROM t2) 
 UNION
(SELECT c FROM t3 UNION ALL SELECT d FROM t4)
Supports for statements with nested UNIONs will be
added in a future version.
This commit is contained in:
gkodinov/kgeorge@magare.gmz
2007-11-26 13:36:24 +02:00
parent 02b913ad26
commit 55afc5c201
3 changed files with 72 additions and 37 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
mysql-test/t/subselect.test
View File

@ -2448,12 +2448,16 @@ 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)));
@ -2461,7 +2465,9 @@ 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));
@ -3002,4 +3008,27 @@ INSERT INTO t2 VALUES (103, 203);
SELECT ((a1,a2) IN (SELECT * FROM t2 WHERE b2 > 0)) IS NULL FROM t1;
DROP TABLE t1, t2;
#
# 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.