Fix for bug #28837: MyISAM storage engine error (134) doing delete with

self-join

When doing DELETE with self-join on a MyISAM or MERGE table, it could
happen that a record being retrieved in join_read_next_same() has
already been deleted by previous iterations. That caused the engine's
index_next_same() method to fail with HA_ERR_RECORD_DELETED error and
the whole DELETE query to be aborted with an error.

Fixed by suppressing the HA_ERR_RECORD_DELETED error in
hy_myisam::index_next_same() and ha_myisammrg::index_next_same(). Since
HA_ERR_RECORD_DELETED can only be returned by MyISAM, there is no point
in filtering this error in the SQL layer.

1 files changed, 17 insertions, 0 deletions

diff --git a/mysql-test/t/myisam.test b/mysql-test/t/myisam.test
index d5f403616c8..ab00af4cc1a 100644
--- a/mysql-test/t/myisam.test
+++ b/mysql-test/t/myisam.test
@@ -1161,4 +1161,21 @@ ALTER TABLE t1 ENABLE KEYS;
 SELECT a FROM t1 FORCE INDEX (inx) WHERE a=1;
 DROP TABLE t1;
 
+#
+# Bug#28837: MyISAM storage engine error (134) doing delete with self-join
+#
+
+CREATE TABLE t1 (id int NOT NULL, ref int NOT NULL, INDEX (id)) ENGINE=MyISAM;
+CREATE TABLE t2 LIKE t1;
+
+INSERT INTO t2 (id, ref) VALUES (1,3), (2,1), (3,2), (4,5), (4,4);
+INSERT INTO t1 SELECT * FROM t2;
+
+SELECT * FROM t1 AS a INNER JOIN t1 AS b USING (id) WHERE a.ref < b.ref;
+SELECT * FROM t1;
+DELETE FROM a USING t1 AS a INNER JOIN t1 AS b USING (id) WHERE a.ref < b.ref;
+SELECT * FROM t1;
+
+DROP TABLE t1, t2;
+
 --echo End of 5.0 tests