Commit c1fd20bb authored by unknown's avatar unknown
Browse files

null.test, null.result: 

  Added test case for bug #4256.
join_outer.result:
  Fixed bug #4256.
item_cmpfunc.h:
  Fixed inconsistency of values of used_tables_cache and
  const_item_cache for Item_func_isnull objects.
  This inconsistency caused bug #4256.


sql/item_cmpfunc.h:
  Fixed inconsistency of values of used_tables_cache and
  const_item_cache for Item_func_isnull objects.
  This inconsistency caused bug #4256.
mysql-test/r/join_outer.result:
  Fixed bug #4256.
mysql-test/r/null.result:
  Added test case for bug #4256.
mysql-test/t/null.test:
  Added test case for bug #4256.
parent 4f0e2da3

mysql-test/r/join_outer.result

+1 −1
Original line number Diff line number Diff line
@@ -91,7 +91,7 @@ grp a c id a c d 
NULL	NULL		NULL	NULL	NULL	NULL

explain select t1.*,t2.* from t1,t2 where t1.a=t2.a and isnull(t2.a)=1;

Comment

Impossible WHERE noticed after reading const tables

Impossible WHERE

explain select t1.*,t2.* from t1 left join t2 on t1.a=t2.a where isnull(t2.a)=1;

table	type	possible_keys	key	key_len	ref	rows	Extra

t1	ALL	NULL	NULL	NULL	NULL	7

mysql-test/r/null.result

+19 −0
Original line number Diff line number Diff line
@@ -109,3 +109,22 @@ a b c d 
	0	0000-00-00 00:00:00	0

	0	0000-00-00 00:00:00	0

drop table t1;

CREATE TABLE t1(i int, KEY(i));

INSERT INTO t1 VALUES(1);

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

EXPLAIN SELECT * FROM t1 WHERE i=2 OR i IS NULL;

table	type	possible_keys	key	key_len	ref	rows	Extra

t1	range	i	i	5	NULL	10	Using where; Using index

ALTER TABLE t1 CHANGE i i int NOT NULL;

EXPLAIN SELECT * FROM t1 WHERE i=2 OR i IS NULL;

table	type	possible_keys	key	key_len	ref	rows	Extra

t1	range	i	i	4	NULL	7	Using where; Using index

DROP TABLE t1;

mysql-test/t/null.test

+23 −0
Original line number Diff line number Diff line
@@ -79,3 +79,26 @@ INSERT INTO t1 (d) values (null),(null); 
select * from t1;

drop table t1;



# Test case for bug #4256



CREATE TABLE t1(i int, KEY(i));



INSERT INTO t1 VALUES(1);



INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;

INSERT INTO t1 SELECT i*2 FROM t1;



EXPLAIN SELECT * FROM t1 WHERE i=2 OR i IS NULL;



ALTER TABLE t1 CHANGE i i int NOT NULL;



EXPLAIN SELECT * FROM t1 WHERE i=2 OR i IS NULL;



DROP TABLE t1;

sql/item_cmpfunc.h

+1 −0
Original line number Diff line number Diff line
@@ -469,6 +469,7 @@ class Item_func_isnull :public Item_bool_func 
    if (!args[0]->maybe_null)

    {

      used_tables_cache= 0;			/* is always false */

      const_item_cache= 1;

      cached_value= (longlong) 0;

    }

    else