Fixed LP bug #922971.

Applied the fix for bug #12546542 from the mysql-5.6 code line:
JOIN_CACHE::join_records forgot to reset JOIN_TAB::first_unmatched
in some cases.

1 files changed, 42 insertions, 0 deletions

diff --git a/mysql-test/t/join_cache.test b/mysql-test/t/join_cache.test
index cc1941e16b9..8a61c00b7d4 100644
--- a/mysql-test/t/join_cache.test
+++ b/mysql-test/t/join_cache.test
@@ -3505,5 +3505,47 @@ set optimizer_switch=@tmp_optimizer_switch;
 
 DROP TABLE t1,t2,t3;
 
+--echo #
+--echo # Bug #12546542: missing row with semijoin=off + join cache
+--echo # (LP bug #922971)
+--echo #
+
+CREATE TABLE t1 (a varchar(1024));
+INSERT INTO t1 VALUES ('v'), ('we');
+CREATE TABLE t2 (
+  a varchar(1024) CHARACTER SET utf8 DEFAULT NULL, b int, c int
+);
+INSERT INTO t2 VALUES ('we',4,NULL), ('v',1305673728,6);
+CREATE TABLE t3 (b int, c int);
+INSERT INTO t3 VALUES (4,4);
+
+set @tmp_optimizer_switch=@@optimizer_switch;
+set optimizer_switch='semijoin=off';
+set optimizer_switch='materialization=off';
+
+set join_cache_level=0;
+EXPLAIN
+SELECT * FROM t1
+  WHERE a IN (SELECT t2.a FROM t2 LEFT JOIN t3 ON t2.b = t3.b 
+                WHERE t2.c < 10 OR t3.c > 1);
+
+SELECT * FROM t1
+  WHERE a IN (SELECT t2.a FROM t2 LEFT JOIN t3 ON t2.b = t3.b 
+                WHERE t2.c < 10 OR t3.c > 1);
+
+set join_cache_level=2;
+EXPLAIN
+SELECT * FROM t1
+  WHERE a IN (SELECT t2.a FROM t2 LEFT JOIN t3 ON t2.b = t3.b
+                WHERE t2.c < 10 OR t3.c > 1);
+SELECT * FROM t1
+  WHERE a IN (SELECT t2.a FROM t2 LEFT JOIN t3 ON t2.b = t3.b
+                WHERE t2.c < 10 OR t3.c > 1);
+
+set join_cache_level = default;
+set optimizer_switch=@tmp_optimizer_switch;
+
+DROP TABLE t1,t2,t3;
+
 # this must be the last command in the file
 set @@optimizer_switch=@save_optimizer_switch;