Commit 9ec81018 authored by igor@rurik.mysql.com's avatar igor@rurik.mysql.com
Browse files

Fixed bug #19816. 

This bug was introduced when the patch resolving the
performance problem 17164 was applied. As a result
of that modification the not_null_tables attributes
were calculated incorrectly for constant OR conditions.
This triggered invalid conversion of outer joins into
inner joins.
parent 767d25da

mysql-test/r/join_outer.result

+37 −2
Original line number Diff line number Diff line
@@ -1151,8 +1151,8 @@ EXPLAIN 
SELECT COUNT(*) FROM t2 LEFT JOIN t1 ON t2.fkey = t1.id 

WHERE t1.name LIKE 'A%' OR FALSE;

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t1	index	PRIMARY,name	name	23	NULL	3	Using where; Using index

1	SIMPLE	t2	ref	fkey	fkey	5	test.t1.id	1	Using where; Using index

1	SIMPLE	t2	index	NULL	fkey	5	NULL	5	Using index

1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.fkey	1	Using where

DROP TABLE t1,t2;

DROP VIEW IF EXISTS v1,v2;

DROP TABLE IF EXISTS t1,t2;
@@ -1176,3 +1176,38 @@ a b 
3	3

DROP VIEW v1,v2;

DROP TABLE t1,t2;

CREATE TABLE t1 (a int);

CREATE TABLE t2 (b int);

INSERT INTO t1 VALUES (1), (2), (3), (4);

INSERT INTO t2 VALUES (2), (3);

SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1);

a	b

1	NULL

2	2

3	3

4	NULL

SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1 OR 1);

a	b

1	NULL

2	2

3	3

4	NULL

SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (0 OR 1);

a	b

1	NULL

2	2

3	3

4	NULL

SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1 OR 2=2);

a	b

1	NULL

2	2

3	3

4	NULL

SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1 OR 1=0);

a	b

1	NULL

2	2

3	3

4	NULL

DROP TABLE t1,t2;

mysql-test/t/join_outer.test

+18 −0
Original line number Diff line number Diff line
@@ -805,3 +805,21 @@ SELECT v1.a, v2. b 


DROP VIEW v1,v2;

DROP TABLE t1,t2;



#

# Bug 19816: LEFT OUTER JOIN with constant ORed predicates in WHERE clause

# 



CREATE TABLE t1 (a int);

CREATE TABLE t2 (b int);

INSERT INTO t1 VALUES (1), (2), (3), (4);

INSERT INTO t2 VALUES (2), (3);



SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1);



SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1 OR 1);

SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (0 OR 1);

SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1 OR 2=2);

SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1 OR 1=0);



DROP TABLE t1,t2;

sql/item_cmpfunc.cc

+3 −1
Original line number Diff line number Diff line
@@ -2570,7 +2570,9 @@ Item_cond::fix_fields(THD *thd, Item **ref) 
	(item= *li.ref())->check_cols(1))

      return TRUE; /* purecov: inspected */

    used_tables_cache|=     item->used_tables();

    if (!item->const_item())

    if (item->const_item())

      and_tables_cache= (table_map) 0;

    else

    {

      tmp_table_map= item->not_null_tables();

      not_null_tables_cache|= tmp_table_map;