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

Fixed bug #28272: crash that occurs when running an EXPLAIN command

for a query over an empty table right after its creation. 
The crash is the result of an attempt made by JOIN::optimize to evaluate
the WHERE condition when no records have been actually read.
The added test case can reproduce the crash only with InnoDB tables and
only with 5.0.x.
This commit is contained in:
igor@olga.mysql.com
2007-05-14 23:55:18 -07:00
parent d71043b889
commit 268be06874
3 changed files with 52 additions and 0 deletions

View File

@ -161,4 +161,25 @@ SELECT * FROM t1;
c1 cnt
1a 2
DROP TABLE t1;
CREATE TABLE t1 (
a1 decimal(10,0) DEFAULT NULL,
a2 blob,
a3 time DEFAULT NULL,
a4 blob,
a5 char(175) DEFAULT NULL,
a6 timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
a7 tinyblob,
INDEX idx (a6,a7(239),a5)
) ENGINE=InnoDB;
EXPLAIN SELECT a4 FROM t1 WHERE
a6=NULL AND
a4='UNcT5pIde4I6c2SheTo4gt92OV1jgJCVkXmzyf325R1DwLURkbYHwhydANIZMbKTgdcR5xS';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
EXPLAIN SELECT t1.a4 FROM t1, t1 t WHERE
t.a6=t.a6 AND t1.a6=NULL AND
t1.a4='UNcT5pIde4I6c2SheTo4gt92OV1jgJCVkXmzyf325R1DwLURkbYHwhydANIZMbKTgdcR5xS';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
DROP TABLE t1;
End of 4.1 tests