Fixed LP bug #813447.

Do not make substitution of a single-row table if it is an inner
table of an outer join with on expression containing an expensive
subquery.

mysql-test/r/join_outer.result

@@ -1539,3 +1539,25 @@ GROUP BY t2.f1, t2.f2;
 f1	f1	f2
 DROP TABLE t1,t2;
 End of 5.1 tests
+#
+# LP bug #813447: LEFT JOIN with single-row inner table and
+#                 a subquery in ON expression
+#
+CREATE TABLE t1 (a int);
+INSERT INTO t1 VALUES (0);
+CREATE TABLE t2 (a int);
+INSERT INTO t2 VALUES (0);
+CREATE TABLE t3 (a int);
+INSERT INTO t3 VALUES (0), (0);
+SELECT t2.a FROM t1 LEFT JOIN t2 ON (6) IN (SELECT a FROM t3);
+a
+NULL
+EXPLAIN EXTENDED
+SELECT t2.a FROM t1 LEFT JOIN t2 ON (6) IN (SELECT a FROM t3);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	1	100.00	Using where
+2	DEPENDENT SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t1` left join `test`.`t2` on(<in_optimizer>(6,<exists>(select `test`.`t3`.`a` from `test`.`t3` where (6 = `test`.`t3`.`a`)))) where 1
+DROP TABLE t1,t2,t3;

mysql-test/r/join_outer_jcl6.result

@@ -1548,6 +1548,28 @@ GROUP BY t2.f1, t2.f2;
 f1	f1	f2
 DROP TABLE t1,t2;
 End of 5.1 tests
+#
+# LP bug #813447: LEFT JOIN with single-row inner table and
+#                 a subquery in ON expression
+#
+CREATE TABLE t1 (a int);
+INSERT INTO t1 VALUES (0);
+CREATE TABLE t2 (a int);
+INSERT INTO t2 VALUES (0);
+CREATE TABLE t3 (a int);
+INSERT INTO t3 VALUES (0), (0);
+SELECT t2.a FROM t1 LEFT JOIN t2 ON (6) IN (SELECT a FROM t3);
+a
+NULL
+EXPLAIN EXTENDED
+SELECT t2.a FROM t1 LEFT JOIN t2 ON (6) IN (SELECT a FROM t3);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	1	100.00	Using where
+2	DEPENDENT SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t1` left join `test`.`t2` on(<in_optimizer>(6,<exists>(select `test`.`t3`.`a` from `test`.`t3` where (6 = `test`.`t3`.`a`)))) where 1
+DROP TABLE t1,t2,t3;
 set join_cache_level=default;
 show variables like 'join_cache_level';
 Variable_name	Value

mysql-test/r/subselect_mat.result

@@ -1409,7 +1409,7 @@ EXPLAIN
 SELECT i FROM t1 LEFT JOIN t2 ON (j) IN (SELECT k FROM t3);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
-1	PRIMARY	t2	system	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	1	Using where
 2	SUBQUERY	t3	system	NULL	NULL	NULL	NULL	0	const row not found
 SELECT i FROM t1 LEFT JOIN t2 ON (j) IN (SELECT k FROM t3);
 i
@@ -1418,7 +1418,7 @@ EXPLAIN
 SELECT i FROM t1 LEFT JOIN t2 ON (j) IN (SELECT max(k) FROM t3);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
-1	PRIMARY	t2	system	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	1	Using where
 2	SUBQUERY	t3	system	NULL	NULL	NULL	NULL	0	const row not found
 SELECT i FROM t1 LEFT JOIN t2 ON (j) IN (SELECT max(k) FROM t3);
 i
@@ -1437,10 +1437,10 @@ SELECT *
 FROM t2 LEFT JOIN t2 t3 ON (8, 4) IN (SELECT c1, c1 FROM t1)";
 EXECUTE st1;
 c2	c2
-10	10
+10	NULL
 EXECUTE st1;
 c2	c2
-10	10
+10	NULL
 DROP TABLE t1, t2;
 # 
 # Testcase backport: BUG#46548 IN-subqueries return 0 rows with materialization=on

mysql-test/t/join_outer.test

@@ -1106,3 +1106,24 @@ GROUP BY t2.f1, t2.f2;
 DROP TABLE t1,t2;
 
 --echo End of 5.1 tests
+
+--echo #
+--echo # LP bug #813447: LEFT JOIN with single-row inner table and
+--echo #                 a subquery in ON expression
+--echo #
+
+CREATE TABLE t1 (a int);
+INSERT INTO t1 VALUES (0);
+
+CREATE TABLE t2 (a int);
+INSERT INTO t2 VALUES (0);
+
+CREATE TABLE t3 (a int);
+INSERT INTO t3 VALUES (0), (0);
+
+SELECT t2.a FROM t1 LEFT JOIN t2 ON (6) IN (SELECT a FROM t3);
+EXPLAIN EXTENDED
+SELECT t2.a FROM t1 LEFT JOIN t2 ON (6) IN (SELECT a FROM t3);
+
+DROP TABLE t1,t2,t3;
+

sql/sql_select.cc

@@ -3268,7 +3268,9 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
 	  continue;
 	if (table->file->stats.records <= 1L &&
 	    (table->file->ha_table_flags() & HA_STATS_RECORDS_IS_EXACT) &&
-            !table->pos_in_table_list->embedding)
+            !table->pos_in_table_list->embedding &&
+	      !((outer_join & table->map) && 
+		(*s->on_expr_ref)->is_expensive()))
 	{					// system table
 	  int tmp= 0;
 	  s->type=JT_SYSTEM;