Fixed LP bug #702301.

The function matching_cond should take into account that
there may be always false constant conjunctive conditions
that has not been evaluated yet,for example, conjunctive
conditions with non-correlated subqueries.

mysql-test/r/myisam_mrr.result

@@ -349,10 +349,10 @@ WHERE t2.int_key IS NULL
 GROUP BY t2.pk
 );
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	100.00	
 2	SUBQUERY	t2	ref	int_key	int_key	5	const	1	100.00	Using index condition; Using where; Using filesort
 Warnings:
-Note	1003	select min(`test`.`t1`.`pk`) AS `MIN(t1.pk)` from `test`.`t1` where exists(select `test`.`t2`.`pk` from `test`.`t2` where isnull(`test`.`t2`.`int_key`) group by `test`.`t2`.`pk`)
+Note	1003	select min(1) AS `MIN(t1.pk)` from `test`.`t1` where exists(select `test`.`t2`.`pk` from `test`.`t2` where isnull(`test`.`t2`.`int_key`) group by `test`.`t2`.`pk`)
 DROP TABLE t1, t2;
 #
 # BUG#42048 Discrepancy between MyISAM and Maria's ICP implementation

mysql-test/r/subselect_mat.result

@@ -1150,43 +1150,48 @@ create table t2 (b1 int);
 insert into t1 values (5);
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
 2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	const row not found
 select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 min(a1)
+NULL
 set @save_optimizer_switch=@@optimizer_switch;
 set @@optimizer_switch=@optimizer_switch_local_default;
 set @@optimizer_switch='materialization=off,in_to_exists=on';
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
 2	DEPENDENT SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	const row not found
 select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 min(a1)
+NULL
 set @@optimizer_switch=@optimizer_switch_local_default;
 set @@optimizer_switch='semijoin=off';
 explain select min(a1) from t1 where 7 in (select b1 from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
 2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	const row not found
 select min(a1) from t1 where 7 in (select b1 from t2);
 min(a1)
+NULL
 set @@optimizer_switch=@optimizer_switch_local_default;
 set @@optimizer_switch='materialization=off,in_to_exists=on';
 # with MariaDB and MWL#90, this particular case is solved:
 explain select min(a1) from t1 where 7 in (select b1 from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
 2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 select min(a1) from t1 where 7 in (select b1 from t2);
 min(a1)
+NULL
 # but when we go around MWL#90 code, the problem still shows up:
 explain select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
 2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 min(a1)
+NULL
 set @@optimizer_switch= @save_optimizer_switch;
 drop table t1,t2;
 create table t1 (a char(2), b varchar(10));
@@ -1555,3 +1560,33 @@ FROM t2;
 (SELECT COUNT(DISTINCT f2), f1, f3 FROM t1 GROUP BY f1, f3)
 1
 drop table t1, t2;
+#
+# LPBUG#702301: MAX in select + always false WHERE with SQ
+#
+CREATE TABLE t1 (a int, b int, KEY (b));
+INSERT INTO t1 VALUES (3,1), (4,2);
+CREATE TABLE t2 (a int);
+INSERT INTO t2 VALUES (7), (8);
+set @@optimizer_switch='materialization=on,in_to_exists=off,semijoin=off';
+SELECT MAX(t1.b) AS max_res FROM t1 WHERE (9) IN (SELECT a FROM t2);
+max_res
+NULL
+EXPLAIN EXTENDED
+SELECT MAX(t1.b) AS max_res FROM t1 WHERE (9) IN (SELECT a FROM t2);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t1	index	NULL	b	5	NULL	2	100.00	Using index
+2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	
+Warnings:
+Note	1003	select max(`test`.`t1`.`b`) AS `max_res` from `test`.`t1` where <in_optimizer>(9,9 in ( <materialize> (select `test`.`t2`.`a` from `test`.`t2` ), <primary_index_lookup>(9 in <temporary table> on distinct_key where ((9 = `<subquery2>`.`a`)))))
+set @@optimizer_switch='materialization=off,in_to_exists=on,semijoin=off';
+SELECT MAX(t1.b) AS max_res FROM t1 WHERE (9) IN (SELECT a FROM t2);
+max_res
+NULL
+EXPLAIN EXTENDED
+SELECT MAX(t1.b) AS max_res FROM t1 WHERE (9) IN (SELECT a FROM t2);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t1	index	NULL	b	5	NULL	2	100.00	Using index
+2	DEPENDENT SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+Warnings:
+Note	1003	select max(`test`.`t1`.`b`) AS `max_res` from `test`.`t1` where <in_optimizer>(9,<exists>(select `test`.`t2`.`a` from `test`.`t2` where (9 = `test`.`t2`.`a`)))
+DROP TABLE t1,t2;

mysql-test/r/subselect_sj_mat.result

@@ -1196,18 +1196,20 @@ set @@optimizer_switch=@optimizer_switch_local_default;
 set @@optimizer_switch='materialization=off,in_to_exists=on';
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
 2	DEPENDENT SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	const row not found
 select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 min(a1)
+NULL
 set @@optimizer_switch=@optimizer_switch_local_default;
 set @@optimizer_switch='semijoin=off';
 explain select min(a1) from t1 where 7 in (select b1 from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
 2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 select min(a1) from t1 where 7 in (select b1 from t2);
 min(a1)
+NULL
 set @@optimizer_switch=@optimizer_switch_local_default;
 set @@optimizer_switch='materialization=off,in_to_exists=on';
 # with MariaDB and MWL#90, this particular case is solved:
@@ -1220,10 +1222,11 @@ NULL
 # but when we go around MWL#90 code, the problem still shows up:
 explain select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
 2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 min(a1)
+NULL
 set @@optimizer_switch= @save_optimizer_switch;
 drop table t1,t2;
 create table t1 (a char(2), b varchar(10));

mysql-test/t/subselect_mat.test

@@ -202,3 +202,27 @@ SELECT (f1, f2, f3) NOT IN
 FROM t2;
 
 drop table t1, t2;
+
+--echo #
+--echo # LPBUG#702301: MAX in select + always false WHERE with SQ
+--echo #
+
+CREATE TABLE t1 (a int, b int, KEY (b));
+INSERT INTO t1 VALUES (3,1), (4,2);
+CREATE TABLE t2 (a int);
+INSERT INTO t2 VALUES (7), (8);
+
+set @@optimizer_switch='materialization=on,in_to_exists=off,semijoin=off';
+
+SELECT MAX(t1.b) AS max_res FROM t1 WHERE (9) IN (SELECT a FROM t2);
+EXPLAIN EXTENDED
+SELECT MAX(t1.b) AS max_res FROM t1 WHERE (9) IN (SELECT a FROM t2);
+
+set @@optimizer_switch='materialization=off,in_to_exists=on,semijoin=off';
+
+SELECT MAX(t1.b) AS max_res FROM t1 WHERE (9) IN (SELECT a FROM t2);
+EXPLAIN EXTENDED
+SELECT MAX(t1.b) AS max_res FROM t1 WHERE (9) IN (SELECT a FROM t2);
+
+DROP TABLE t1,t2;
+

sql/opt_sum.cc

@@ -623,7 +623,7 @@ static bool matching_cond(bool max_fl, TABLE_REF *ref, KEY *keyinfo,
   if (!(cond->used_tables() & field->table->map))
   {
     /* Condition doesn't restrict the used table */
-    DBUG_RETURN(TRUE);
+    DBUG_RETURN(!cond->const_item());
   }
   if (cond->type() == Item::COND_ITEM)
   {