Fixed bug mdev-5028.
Apparently in a general case a short-cut for the distinct optimization is invalid if join buffers are used to join tables after the tables whose values are to selected.
This commit is contained in:
Igor Babaev
parent
ec7da1561e
commit
00816a964f
@ -879,3 +879,113 @@ NULL
|
||||
7
|
||||
drop view v;
|
||||
drop table t1, t2;
|
||||
CREATE TABLE t1 (
|
||||
id int, i1 int, i2 int DEFAULT 0,
|
||||
d1 date DEFAULT '2000-01-01', d2 date DEFAULT '2000-01-01',
|
||||
t1 time DEFAULT '00:00:00', t2 time DEFAULT '00:00:00',
|
||||
dt1 datetime NOT NULL DEFAULT '2000-01-01 00:00:00',
|
||||
dt2 datetime NOT NULL DEFAULT '2000-01-01 00:00:00',
|
||||
c1 varchar(1) NOT NULL, c2 varchar(1) NOT NULL
|
||||
) ENGINE=MyISAM;
|
||||
CREATE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT * FROM t1;
|
||||
INSERT INTO t1 (id,i1,c1,c2) VALUES
|
||||
(1,7,'t','t'),(2,4,'k','k'),(3,2,'e','e'),(4,0,'i','i'),(5,1,'t','t'),(6,91,'m','m'),
|
||||
(7,6,'z','z'),(8,3,'c','c'),(9,6,'i','i'),(10,8,'v','v'), (11,1,'l','l'),(12,4,'j','j'),
|
||||
(13,5,'w','w'),(14,0,'r','r'),(15,7,'o','o'),(16,9,'o','o'),(17,7,'u','u'),(18,6,'f','f'),
|
||||
(19,0,'l','l'),(20,6,'g','g'),(21,1,'e','e'),(22,7,'y','y'),(23,0,'p','p'),(24,6,'v','v'),
|
||||
(25,5,'d','d'),(26,9,'i','i'),(27,5,'z','z'),(28,2,'q','q'),(29,4,'j','j'),(30,9,'m','m'),
|
||||
(31,8,'d','d'),(32,5,'r','r'),(33,1,'r','r'),(34,1,'k','k'),(35,4,'p','p'),(36,2,'x','x'),
|
||||
(37,5,'w','w'),(38,0,'k','k'),(39,7,'y','y'),(40,4,'p','p'),(41,9,'l','l'),(42,2,'u','u'),
|
||||
(43,3,'r','r'),(44,5,'y','y'),(45,3,'u','u'),(46,9,'t','t'),(47,8,'f','f'),(48,2,'f','f'),
|
||||
(49,2,'q','q'),(50,6,'v','v'),(51,6,'u','u'),(52,0,'b','b'),(53,1,'n','n'),(54,2,'p','p'),
|
||||
(55,0,'y','y'),(56,1,'l','l'),(57,1,'c','c'),(58,0,'d','d'),(59,2,'y','y'),(60,7,'l','l'),
|
||||
(61,6,'m','m'),(62,9,'q','q'),(63,0,'j','j'),(64,3,'u','u'),(65,4,'w','w'),(66,5,'p','p'),
|
||||
(67,8,'z','z'),(68,5,'u','u'),(69,7,'b','b'),(70,0,'f','f'),(71,6,'u','u'),(72,1,'i','i'),
|
||||
(73,9,'s','s'),(74,3,'y','y'),(75,5,'s','s'),(76,8,'x','x'),(77,3,'s','s'),(78,3,'l','l'),
|
||||
(79,8,'b','b'),(80,0,'p','p'),(81,9,'m','m'),(82,5,'k','k'),(83,7,'u','u'),(84,0,'y','y'),
|
||||
(85,2,'x','x'),(86,5,'h','h'),(87,5,'j','j'),(88,5,'o','o'),(89,9,'o','o'),(90,1,'c','c'),
|
||||
(91,7,'k','k'),(92,9,'t','t'),(93,3,'h','h'),(94,6,'g','g'),(95,9,'r','r'),(96,2,'i','i');
|
||||
CREATE TABLE t2 (i INT) ENGINE=MyISAM;
|
||||
INSERT INTO t2 VALUES (7),(8);
|
||||
SELECT STRAIGHT_JOIN COUNT(DISTINCT t1.id) FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
COUNT(DISTINCT t1.id)
|
||||
18
|
||||
EXPLAIN EXTENDED
|
||||
SELECT STRAIGHT_JOIN DISTINCT t1.id FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
id select_type table type possible_keys key key_len ref rows filtered Extra
|
||||
1 PRIMARY t1 ALL NULL NULL NULL NULL 96 100.00 Using where; Using temporary
|
||||
1 PRIMARY <derived2> ref key0 key0 5 test.t1.i1 9 100.00 Using where; Distinct
|
||||
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where; Distinct; Using join buffer (flat, BNL join)
|
||||
2 DERIVED t1 ALL NULL NULL NULL NULL 96 100.00
|
||||
Warnings:
|
||||
Note 1003 select straight_join distinct `test`.`t1`.`id` AS `id` from `test`.`t1` join `test`.`v1` join `test`.`t2` where ((`test`.`t2`.`i` = `v1`.`id`) and (`v1`.`i1` = `test`.`t1`.`i1`) and (`v1`.`id` <> 3))
|
||||
set join_buffer_size=1024;
|
||||
SELECT STRAIGHT_JOIN DISTINCT t1.id FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
id
|
||||
7
|
||||
8
|
||||
9
|
||||
18
|
||||
20
|
||||
24
|
||||
43
|
||||
45
|
||||
50
|
||||
51
|
||||
61
|
||||
64
|
||||
71
|
||||
74
|
||||
77
|
||||
78
|
||||
93
|
||||
94
|
||||
set join_buffer_size=1024*16;
|
||||
SELECT STRAIGHT_JOIN DISTINCT t1.id FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
id
|
||||
7
|
||||
9
|
||||
18
|
||||
20
|
||||
24
|
||||
8
|
||||
50
|
||||
51
|
||||
61
|
||||
43
|
||||
45
|
||||
71
|
||||
64
|
||||
74
|
||||
77
|
||||
78
|
||||
94
|
||||
93
|
||||
set join_buffer_size=default;
|
||||
SELECT STRAIGHT_JOIN DISTINCT t1.id FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
id
|
||||
7
|
||||
9
|
||||
18
|
||||
20
|
||||
24
|
||||
50
|
||||
51
|
||||
61
|
||||
71
|
||||
94
|
||||
8
|
||||
43
|
||||
45
|
||||
64
|
||||
74
|
||||
77
|
||||
78
|
||||
93
|
||||
DROP VIEW v1;
|
||||
DROP TABLE t1,t2;
|
||||
|
||||
@ -682,3 +682,62 @@ select * from v;
|
||||
select distinct (select max(a) from t1 where alias.b = a) as field1 from t2 as alias group by field1;
|
||||
drop view v;
|
||||
drop table t1, t2;
|
||||
|
||||
#
|
||||
# Bug mdev-5028: invalid distinct optimization when join buffer is used
|
||||
#
|
||||
|
||||
CREATE TABLE t1 (
|
||||
id int, i1 int, i2 int DEFAULT 0,
|
||||
d1 date DEFAULT '2000-01-01', d2 date DEFAULT '2000-01-01',
|
||||
t1 time DEFAULT '00:00:00', t2 time DEFAULT '00:00:00',
|
||||
dt1 datetime NOT NULL DEFAULT '2000-01-01 00:00:00',
|
||||
dt2 datetime NOT NULL DEFAULT '2000-01-01 00:00:00',
|
||||
c1 varchar(1) NOT NULL, c2 varchar(1) NOT NULL
|
||||
) ENGINE=MyISAM;
|
||||
|
||||
CREATE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT * FROM t1;
|
||||
|
||||
INSERT INTO t1 (id,i1,c1,c2) VALUES
|
||||
(1,7,'t','t'),(2,4,'k','k'),(3,2,'e','e'),(4,0,'i','i'),(5,1,'t','t'),(6,91,'m','m'),
|
||||
(7,6,'z','z'),(8,3,'c','c'),(9,6,'i','i'),(10,8,'v','v'), (11,1,'l','l'),(12,4,'j','j'),
|
||||
(13,5,'w','w'),(14,0,'r','r'),(15,7,'o','o'),(16,9,'o','o'),(17,7,'u','u'),(18,6,'f','f'),
|
||||
(19,0,'l','l'),(20,6,'g','g'),(21,1,'e','e'),(22,7,'y','y'),(23,0,'p','p'),(24,6,'v','v'),
|
||||
(25,5,'d','d'),(26,9,'i','i'),(27,5,'z','z'),(28,2,'q','q'),(29,4,'j','j'),(30,9,'m','m'),
|
||||
(31,8,'d','d'),(32,5,'r','r'),(33,1,'r','r'),(34,1,'k','k'),(35,4,'p','p'),(36,2,'x','x'),
|
||||
(37,5,'w','w'),(38,0,'k','k'),(39,7,'y','y'),(40,4,'p','p'),(41,9,'l','l'),(42,2,'u','u'),
|
||||
(43,3,'r','r'),(44,5,'y','y'),(45,3,'u','u'),(46,9,'t','t'),(47,8,'f','f'),(48,2,'f','f'),
|
||||
(49,2,'q','q'),(50,6,'v','v'),(51,6,'u','u'),(52,0,'b','b'),(53,1,'n','n'),(54,2,'p','p'),
|
||||
(55,0,'y','y'),(56,1,'l','l'),(57,1,'c','c'),(58,0,'d','d'),(59,2,'y','y'),(60,7,'l','l'),
|
||||
(61,6,'m','m'),(62,9,'q','q'),(63,0,'j','j'),(64,3,'u','u'),(65,4,'w','w'),(66,5,'p','p'),
|
||||
(67,8,'z','z'),(68,5,'u','u'),(69,7,'b','b'),(70,0,'f','f'),(71,6,'u','u'),(72,1,'i','i'),
|
||||
(73,9,'s','s'),(74,3,'y','y'),(75,5,'s','s'),(76,8,'x','x'),(77,3,'s','s'),(78,3,'l','l'),
|
||||
(79,8,'b','b'),(80,0,'p','p'),(81,9,'m','m'),(82,5,'k','k'),(83,7,'u','u'),(84,0,'y','y'),
|
||||
(85,2,'x','x'),(86,5,'h','h'),(87,5,'j','j'),(88,5,'o','o'),(89,9,'o','o'),(90,1,'c','c'),
|
||||
(91,7,'k','k'),(92,9,'t','t'),(93,3,'h','h'),(94,6,'g','g'),(95,9,'r','r'),(96,2,'i','i');
|
||||
|
||||
CREATE TABLE t2 (i INT) ENGINE=MyISAM;
|
||||
INSERT INTO t2 VALUES (7),(8);
|
||||
|
||||
SELECT STRAIGHT_JOIN COUNT(DISTINCT t1.id) FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
|
||||
EXPLAIN EXTENDED
|
||||
SELECT STRAIGHT_JOIN DISTINCT t1.id FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
|
||||
set join_buffer_size=1024;
|
||||
SELECT STRAIGHT_JOIN DISTINCT t1.id FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
|
||||
set join_buffer_size=1024*16;
|
||||
SELECT STRAIGHT_JOIN DISTINCT t1.id FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
|
||||
set join_buffer_size=default;
|
||||
SELECT STRAIGHT_JOIN DISTINCT t1.id FROM
|
||||
t1, v1, t2 WHERE v1.id = t2.i AND t1.i1 = v1.i1 AND t2.i != 3;
|
||||
|
||||
DROP VIEW v1;
|
||||
DROP TABLE t1,t2;
|
||||
|
||||
|
||||
@ -398,7 +398,7 @@ Sensitive_cursor::open(JOIN *join_arg)
|
||||
#ifndef DBUG_OFF
|
||||
JOIN_TAB *first_tab= first_linear_tab(join, WITHOUT_CONST_TABLES);
|
||||
DBUG_ASSERT(first_tab->table->reginfo.not_exists_optimize == 0);
|
||||
DBUG_ASSERT(first_tab->not_used_in_distinct == 0);
|
||||
DBUG_ASSERT(first_tab->shortcut_for_distinct == 0);
|
||||
/*
|
||||
null_row is set only if row not found and it's outer join: should never
|
||||
happen for the first table in join_tab list
|
||||
|
||||
@ -1811,9 +1811,10 @@ int JOIN::init_execution()
|
||||
JOIN_TAB *last_join_tab= join_tab + top_join_tab_count - 1;
|
||||
do
|
||||
{
|
||||
if (used_tables & last_join_tab->table->map)
|
||||
if (used_tables & last_join_tab->table->map ||
|
||||
last_join_tab->use_join_cache)
|
||||
break;
|
||||
last_join_tab->not_used_in_distinct=1;
|
||||
last_join_tab->shortcut_for_distinct= true;
|
||||
} while (last_join_tab-- != join_tab);
|
||||
/* Optimize "select distinct b from t1 order by key_part_1 limit #" */
|
||||
if (order && skip_sort_order)
|
||||
@ -7983,7 +7984,7 @@ JOIN::make_simple_join(JOIN *parent, TABLE *temp_table)
|
||||
join_tab->last_inner= 0;
|
||||
join_tab->first_unmatched= 0;
|
||||
join_tab->ref.key = -1;
|
||||
join_tab->not_used_in_distinct=0;
|
||||
join_tab->shortcut_for_distinct= false;
|
||||
join_tab->read_first_record= join_init_read_record;
|
||||
join_tab->preread_init_done= FALSE;
|
||||
join_tab->join= this;
|
||||
@ -16223,7 +16224,7 @@ static enum_nested_loop_state
|
||||
evaluate_join_record(JOIN *join, JOIN_TAB *join_tab,
|
||||
int error)
|
||||
{
|
||||
bool not_used_in_distinct=join_tab->not_used_in_distinct;
|
||||
bool shortcut_for_distinct= join_tab->shortcut_for_distinct;
|
||||
ha_rows found_records=join->found_records;
|
||||
COND *select_cond= join_tab->select_cond;
|
||||
bool select_cond_result= TRUE;
|
||||
@ -16362,7 +16363,7 @@ evaluate_join_record(JOIN *join, JOIN_TAB *join_tab,
|
||||
was not in the field list; In this case we can abort if
|
||||
we found a row, as no new rows can be added to the result.
|
||||
*/
|
||||
if (not_used_in_distinct && found_records != join->found_records)
|
||||
if (shortcut_for_distinct && found_records != join->found_records)
|
||||
DBUG_RETURN(NESTED_LOOP_NO_MORE_ROWS);
|
||||
}
|
||||
else
|
||||
|
||||
@ -314,8 +314,9 @@ typedef struct st_join_table {
|
||||
uint used_null_fields;
|
||||
uint used_uneven_bit_fields;
|
||||
enum join_type type;
|
||||
bool cached_eq_ref_table,eq_ref_table,not_used_in_distinct;
|
||||
bool sorted;
|
||||
bool cached_eq_ref_table,eq_ref_table;
|
||||
bool shortcut_for_distinct;
|
||||
bool sorted;
|
||||
/*
|
||||
If it's not 0 the number stored this field indicates that the index
|
||||
scan has been chosen to access the table data and we expect to scan
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user