BUG#752992: Wrong results for a subquery with 'semijoin=on'

- Let advance_sj_state() save the value of JOIN::cur_dups_producing_tables
  in POSITION::prefix_dups_producing_tables, and restore_sj_state() restore
  it.

mysql-test/r/subselect.result

@@ -5046,3 +5046,25 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	4	Using where
 2	DEPENDENT SUBQUERY	t2	ref	idx	idx	5	test.t1.a	2	Using index
 DROP TABLE t1,t2;
+#
+# BUG#752992: Wrong results for a subquery with 'semijoin=on'
+#
+CREATE TABLE t1 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t1 VALUES (11,0);
+INSERT INTO t1 VALUES (12,5);
+INSERT INTO t1 VALUES (15,0);
+CREATE TABLE t2 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t2 VALUES (11,1);
+INSERT INTO t2 VALUES (12,2);
+INSERT INTO t2 VALUES (15,4);
+EXPLAIN SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	PRIMARY	NULL	NULL	NULL	3	Start temporary
+1	PRIMARY	t2	index	NULL	PRIMARY	4	NULL	3	Using index; Using join buffer (flat, BNL join)
+1	PRIMARY	it	eq_ref	PRIMARY	PRIMARY	4	test.t1.pk	1	Using index; End temporary
+SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+pk	i
+11	0
+12	5
+15	0
+DROP table t1,t2;

mysql-test/r/subselect3.result

@@ -1142,15 +1142,15 @@ create table t1 (a int) as select * from t0 where a < 5;
 set @save_max_heap_table_size=@@max_heap_table_size;
 set @@optimizer_switch='firstmatch=off,materialization=off';
 set @@max_heap_table_size= 16384;
-explain select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E);
+explain select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E where a+1 < 10000 + A.a + B.a +C.a+D.a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	E	ALL	NULL	NULL	NULL	NULL	5	Start temporary
 1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
 1	PRIMARY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
-1	PRIMARY	C	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
+1	PRIMARY	C	ALL	NULL	NULL	NULL	NULL	10	Using where; Using join buffer (flat, BNL join)
 1	PRIMARY	D	ALL	NULL	NULL	NULL	NULL	10	Using where; End temporary; Using join buffer (flat, BNL join)
 flush status;
-select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E);
+select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E where a+1 < 10000 + A.a + B.a +C.a+D.a);
 count(*)
 5000
 show status like 'Created_tmp_disk_tables';

mysql-test/r/subselect3_jcl6.result

@@ -1149,15 +1149,15 @@ create table t1 (a int) as select * from t0 where a < 5;
 set @save_max_heap_table_size=@@max_heap_table_size;
 set @@optimizer_switch='firstmatch=off,materialization=off';
 set @@max_heap_table_size= 16384;
-explain select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E);
+explain select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E where a+1 < 10000 + A.a + B.a +C.a+D.a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	E	ALL	NULL	NULL	NULL	NULL	5	Using where; Start temporary
 1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
 1	PRIMARY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (incremental, BNL join)
-1	PRIMARY	C	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (incremental, BNL join)
+1	PRIMARY	C	ALL	NULL	NULL	NULL	NULL	10	Using where; Using join buffer (incremental, BNL join)
 1	PRIMARY	D	hash_ALL	NULL	#hash#$hj	5	test.E.a	10	Using where; End temporary; Using join buffer (incremental, BNLH join)
 flush status;
-select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E);
+select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E where a+1 < 10000 + A.a + B.a +C.a+D.a);
 count(*)
 5000
 show status like 'Created_tmp_disk_tables';

mysql-test/r/subselect_no_mat.result

@@ -5048,6 +5048,28 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	4	Using where
 2	DEPENDENT SUBQUERY	t2	ref	idx	idx	5	test.t1.a	2	Using index
 DROP TABLE t1,t2;
+#
+# BUG#752992: Wrong results for a subquery with 'semijoin=on'
+#
+CREATE TABLE t1 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t1 VALUES (11,0);
+INSERT INTO t1 VALUES (12,5);
+INSERT INTO t1 VALUES (15,0);
+CREATE TABLE t2 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t2 VALUES (11,1);
+INSERT INTO t2 VALUES (12,2);
+INSERT INTO t2 VALUES (15,4);
+EXPLAIN SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	PRIMARY	NULL	NULL	NULL	3	Start temporary
+1	PRIMARY	t2	index	NULL	PRIMARY	4	NULL	3	Using index; Using join buffer (flat, BNL join)
+1	PRIMARY	it	eq_ref	PRIMARY	PRIMARY	4	test.t1.pk	1	Using index; End temporary
+SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+pk	i
+11	0
+12	5
+15	0
+DROP table t1,t2;
 set optimizer_switch=default;
 select @@optimizer_switch like '%materialization=on%';
 @@optimizer_switch like '%materialization=on%'

mysql-test/r/subselect_no_opts.result

@@ -5045,4 +5045,26 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	4	Using where
 2	DEPENDENT SUBQUERY	t2	ref	idx	idx	5	test.t1.a	2	Using index
 DROP TABLE t1,t2;
+#
+# BUG#752992: Wrong results for a subquery with 'semijoin=on'
+#
+CREATE TABLE t1 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t1 VALUES (11,0);
+INSERT INTO t1 VALUES (12,5);
+INSERT INTO t1 VALUES (15,0);
+CREATE TABLE t2 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t2 VALUES (11,1);
+INSERT INTO t2 VALUES (12,2);
+INSERT INTO t2 VALUES (15,4);
+EXPLAIN SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Using where
+2	DEPENDENT SUBQUERY	t2	index	NULL	PRIMARY	4	NULL	3	Using index
+2	DEPENDENT SUBQUERY	it	eq_ref	PRIMARY	PRIMARY	4	func	1	Using index
+SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+pk	i
+11	0
+12	5
+15	0
+DROP table t1,t2;
 set optimizer_switch=default;

mysql-test/r/subselect_no_semijoin.result

@@ -5045,4 +5045,26 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	4	Using where
 2	DEPENDENT SUBQUERY	t2	ref	idx	idx	5	test.t1.a	2	Using index
 DROP TABLE t1,t2;
+#
+# BUG#752992: Wrong results for a subquery with 'semijoin=on'
+#
+CREATE TABLE t1 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t1 VALUES (11,0);
+INSERT INTO t1 VALUES (12,5);
+INSERT INTO t1 VALUES (15,0);
+CREATE TABLE t2 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t2 VALUES (11,1);
+INSERT INTO t2 VALUES (12,2);
+INSERT INTO t2 VALUES (15,4);
+EXPLAIN SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Using where
+2	SUBQUERY	t2	index	NULL	PRIMARY	4	NULL	3	Using index
+2	SUBQUERY	it	index	NULL	PRIMARY	4	NULL	3	Using index; Using join buffer (flat, BNL join)
+SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+pk	i
+11	0
+12	5
+15	0
+DROP table t1,t2;
 set optimizer_switch=default;

mysql-test/t/subselect.test

@@ -4316,3 +4316,20 @@ SELECT * FROM t1
   WHERE EXISTS (SELECT a FROM t2 WHERE t2.a = t1.a);
 
 DROP TABLE t1,t2;
+
+--echo #
+--echo # BUG#752992: Wrong results for a subquery with 'semijoin=on'
+--echo #
+CREATE TABLE t1 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t1 VALUES (11,0);
+INSERT INTO t1 VALUES (12,5);
+INSERT INTO t1 VALUES (15,0);
+CREATE TABLE t2 (pk INTEGER PRIMARY KEY, i INTEGER NOT NULL);
+INSERT INTO t2 VALUES (11,1);
+INSERT INTO t2 VALUES (12,2);
+INSERT INTO t2 VALUES (15,4);
+
+EXPLAIN SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
+
+DROP table t1,t2;

mysql-test/t/subselect3.test

@@ -949,9 +949,9 @@ set @save_max_heap_table_size=@@max_heap_table_size;
 set @@optimizer_switch='firstmatch=off,materialization=off';
 set @@max_heap_table_size= 16384;
 
-explain select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E);
+explain select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E where a+1 < 10000 + A.a + B.a +C.a+D.a);
 flush status;
-select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E);
+select count(*) from t0 A, t0 B, t0 C, t0 D where D.a in (select a from t1 E where a+1 < 10000 + A.a + B.a +C.a+D.a);
 show status like 'Created_tmp_disk_tables';
 set @save_max_heap_table_size=@@max_heap_table_size;
 set @@optimizer_switch=@save_optimizer_switch;

sql/opt_subselect.cc

@@ -1861,6 +1861,7 @@ void advance_sj_state(JOIN *join, table_map remaining_tables,
       }
     }
   }
+  pos->prefix_dups_producing_tables= join->cur_dups_producing_tables;
 }
 
 
@@ -1882,6 +1883,8 @@ void restore_prev_sj_state(const table_map remaining_tables,
       tab->join->cur_sj_inner_tables &= ~emb_sj_nest->sj_inner_tables;
     }
   }
+  POSITION *pos= tab->join->positions + idx;
+  tab->join->cur_dups_producing_tables= pos->prefix_dups_producing_tables;
 }
 
 

sql/sql_select.h

@@ -573,6 +573,8 @@ typedef struct st_position
     semi-join's ON expression so we can correctly account for fanout.
   */
   table_map sjm_scan_need_tables;
+
+  table_map prefix_dups_producing_tables;
 } POSITION;