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|
drop table if exists t0, t1, t2, t3, t4, t5, t6;
drop view if exists v1, v2;
SET @save_optimizer_switch=@@optimizer_switch;
SET optimizer_switch='outer_join_with_cache=off';
create table t1 (a int);
insert into t1 values (0),(1),(2),(3);
create table t0 as select * from t1;
create table t2 (a int primary key, b int)
as select a, a as b from t1 where a in (1,2);
create table t3 (a int primary key, b int)
as select a, a as b from t1 where a in (1,3);
# This will be eliminated:
explain select t1.a from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain extended select t1.a from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 100.00
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where 1
select t1.a from t1 left join t2 on t2.a=t1.a;
a
0
1
2
3
# This will not be eliminated as t2.b is in in select list:
explain select * from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
# This will not be eliminated as t2.b is in in order list:
explain select t1.a from t1 left join t2 on t2.a=t1.a order by t2.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
# This will not be eliminated as t2.b is in group list:
explain select t1.a from t1 left join t2 on t2.a=t1.a group by t2.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
# This will not be eliminated as t2.b is in the WHERE
explain select t1.a from t1 left join t2 on t2.a=t1.a where t2.b < 3 or t2.b is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
# Elimination of multiple tables:
explain select t1.a from t1 left join (t2 join t3) on t2.a=t1.a and t3.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
# Elimination of multiple tables (2):
explain select t1.a from t1 left join (t2 join t3 on t2.b=t3.b) on t2.a=t1.a and t3.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
# Elimination when done within an outer join nest:
explain extended
select t0.*
from
t0 left join (t1 left join (t2 join t3 on t2.b=t3.b) on t2.a=t1.a and
t3.a=t1.a) on t0.a=t1.a;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t0 ALL NULL NULL NULL NULL 4 100.00
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1003 select `test`.`t0`.`a` AS `a` from `test`.`t0` left join (`test`.`t1`) on((`test`.`t1`.`a` = `test`.`t0`.`a`)) where 1
# Elimination with aggregate functions
explain select count(*) from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain select count(1) from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain select count(1) from t1 left join t2 on t2.a=t1.a group by t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
This must not use elimination:
explain select count(1) from t1 left join t2 on t2.a=t1.a group by t2.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where; Using index
drop table t0, t1, t2, t3;
create table t0 ( id integer, primary key (id));
create table t1 (
id integer,
attr1 integer,
primary key (id),
key (attr1)
);
create table t2 (
id integer,
attr2 integer,
fromdate date,
primary key (id, fromdate),
key (attr2,fromdate)
);
insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
insert into t0 select A.id + 10*B.id from t0 A, t0 B where B.id > 0;
insert into t1 select id, id from t0;
insert into t2 select id, id, date_add('2009-06-22', interval id day) from t0;
insert into t2 select id, id+1, date_add('2008-06-22', interval id day) from t0;
create view v1 as
select
f.id, a1.attr1, a2.attr2
from
t0 f
left join t1 a1 on a1.id=f.id
left join t2 a2 on a2.id=f.id and
a2.fromdate=(select MAX(fromdate) from
t2 where id=a2.id);
create view v2 as
select
f.id, a1.attr1, a2.attr2
from
t0 f
left join t1 a1 on a1.id=f.id
left join t2 a2 on a2.id=f.id and
a2.fromdate=(select MAX(fromdate) from
t2 where id=f.id);
This should use one table:
explain select id from v1 where id=2;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY f const PRIMARY PRIMARY 4 const 1 Using index
This should use one table:
explain extended select id from v1 where id in (1,2,3,4);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY f range PRIMARY PRIMARY 4 NULL 4 100.00 Using where; Using index
Warnings:
Note 1276 Field or reference 'test.a2.id' of SELECT #3 was resolved in SELECT #2
Note 1003 select `f`.`id` AS `id` from `test`.`t0` `f` where (`f`.`id` in (1,2,3,4))
This should use facts and a1 tables:
explain extended select id from v1 where attr1 between 12 and 14;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY a1 range PRIMARY,attr1 attr1 5 NULL 2 100.00 Using index condition
1 PRIMARY f eq_ref PRIMARY PRIMARY 4 test.a1.id 1 100.00 Using index
Warnings:
Note 1276 Field or reference 'test.a2.id' of SELECT #3 was resolved in SELECT #2
Note 1003 select `f`.`id` AS `id` from `test`.`t0` `f` join `test`.`t1` `a1` where ((`f`.`id` = `a1`.`id`) and (`a1`.`attr1` between 12 and 14))
This should use facts, a2 and its subquery:
explain extended select id from v1 where attr2 between 12 and 14;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY a2 range PRIMARY,attr2 attr2 5 NULL 5 100.00 Using index condition; Using where
1 PRIMARY f eq_ref PRIMARY PRIMARY 4 test.a2.id 1 100.00 Using index
3 DEPENDENT SUBQUERY t2 ref PRIMARY PRIMARY 4 test.a2.id 2 100.00 Using index
Warnings:
Note 1276 Field or reference 'test.a2.id' of SELECT #3 was resolved in SELECT #2
Note 1003 select `f`.`id` AS `id` from `test`.`t0` `f` join `test`.`t2` `a2` where ((`f`.`id` = `a2`.`id`) and (`a2`.`attr2` between 12 and 14) and (`a2`.`fromdate` = (select max(`test`.`t2`.`fromdate`) from `test`.`t2` where (`test`.`t2`.`id` = `a2`.`id`))))
This should use one table:
explain select id from v2 where id=2;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY f const PRIMARY PRIMARY 4 const 1 Using index
This should use one table:
explain extended select id from v2 where id in (1,2,3,4);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY f range PRIMARY PRIMARY 4 NULL 4 100.00 Using where; Using index
Warnings:
Note 1276 Field or reference 'test.f.id' of SELECT #3 was resolved in SELECT #2
Note 1003 select `f`.`id` AS `id` from `test`.`t0` `f` where (`f`.`id` in (1,2,3,4))
This should use facts and a1 tables:
explain extended select id from v2 where attr1 between 12 and 14;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY a1 range PRIMARY,attr1 attr1 5 NULL 2 100.00 Using index condition
1 PRIMARY f eq_ref PRIMARY PRIMARY 4 test.a1.id 1 100.00 Using index
Warnings:
Note 1276 Field or reference 'test.f.id' of SELECT #3 was resolved in SELECT #2
Note 1003 select `f`.`id` AS `id` from `test`.`t0` `f` join `test`.`t1` `a1` where ((`f`.`id` = `a1`.`id`) and (`a1`.`attr1` between 12 and 14))
This should use facts, a2 and its subquery:
explain extended select id from v2 where attr2 between 12 and 14;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY a2 range PRIMARY,attr2 attr2 5 NULL 5 100.00 Using index condition
1 PRIMARY f eq_ref PRIMARY PRIMARY 4 test.a2.id 1 100.00 Using where; Using index
3 DEPENDENT SUBQUERY t2 ref PRIMARY PRIMARY 4 test.f.id 2 100.00 Using index
Warnings:
Note 1276 Field or reference 'test.f.id' of SELECT #3 was resolved in SELECT #2
Note 1003 select `f`.`id` AS `id` from `test`.`t0` `f` join `test`.`t2` `a2` where ((`f`.`id` = `a2`.`id`) and (`a2`.`attr2` between 12 and 14) and (`a2`.`fromdate` = (select max(`test`.`t2`.`fromdate`) from `test`.`t2` where (`test`.`t2`.`id` = `f`.`id`))))
drop view v1, v2;
drop table t0, t1, t2;
create table t1 (a int);
insert into t1 values (0),(1),(2),(3);
create table t2 (pk1 int, pk2 int, pk3 int, col int, primary key(pk1, pk2, pk3));
insert into t2 select a,a,a,a from t1;
This must use only t1:
explain select t1.* from t1 left join t2 on t2.pk1=t1.a and
t2.pk2=t2.pk1+1 and
t2.pk3=t2.pk2+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
This must use only t1:
explain select t1.* from t1 left join t2 on t2.pk1=t1.a and
t2.pk3=t2.pk1+1 and
t2.pk2=t2.pk3+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
This must use both:
explain select t1.* from t1 left join t2 on t2.pk1=t1.a and
t2.pk3=t2.pk1+1 and
t2.pk2=t2.pk3+t2.col;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
This must use only t1:
explain select t1.* from t1 left join t2 on t2.pk2=t1.a and
t2.pk1=t2.pk2+1 and
t2.pk3=t2.pk1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
drop table t1, t2;
create table t1 (pk int primary key, col int);
insert into t1 values (1,1),(2,2);
create table t2 like t1;
insert into t2 select * from t1;
create table t3 like t1;
insert into t3 select * from t1;
explain
select t1.* from t1 left join ( t2 left join t3 on t3.pk=t2.col) on t2.col=t1.col;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where
explain
select t1.*, t2.* from t1 left join (t2 left join t3 on t3.pk=t2.col) on t2.pk=t1.col;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.col 1 Using where
explain select t1.*
from
t1 left join ( t2 left join t3 on t3.pk=t2.col or t3.pk=t2.col)
on t2.col=t1.col or t2.col=t1.col;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where
explain select t1.*, t2.*
from
t1 left join
(t2 left join t3 on t3.pk=t2.col or t3.pk=t2.col)
on t2.pk=t1.col or t2.pk=t1.col;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.col 1 Using where
drop table t1, t2, t3;
#
# Check things that look like functional dependencies but really are not
#
create table t1 (a char(10) character set latin1 collate latin1_general_ci primary key);
insert into t1 values ('foo');
insert into t1 values ('bar');
create table t2 (a char(10) character set latin1 collate latin1_general_cs primary key);
insert into t2 values ('foo');
insert into t2 values ('FOO');
this must not use table elimination:
explain select t1.* from t1 left join t2 on t2.a='foo' collate latin1_general_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL PRIMARY 10 NULL 2 Using index
1 SIMPLE t2 index PRIMARY PRIMARY 10 NULL 2 Using where; Using index
this must not use table elimination:
explain select t1.* from t1 left join t2 on t2.a=t1.a collate latin1_general_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL PRIMARY 10 NULL 2 Using index
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 2 Range checked for each record (index map: 0x1)
drop table t1,t2;
create table t1 (a int primary key);
insert into t1 values (1),(2);
create table t2 (a char(10) primary key);
insert into t2 values ('1'),('1.0');
this must not use table elimination:
explain select t1.* from t1 left join t2 on t2.a=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL PRIMARY 4 NULL 2 Using index
1 SIMPLE t2 index PRIMARY PRIMARY 10 NULL 2 Using where; Using index
this must not use table elimination:
explain select t1.* from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL PRIMARY 4 NULL 2 Using index
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 2 Range checked for each record (index map: 0x1)
drop table t1, t2;
create table t1 (a char(10) primary key);
insert into t1 values ('foo'),('bar');
create table t2 (a char(10), unique key(a(2)));
insert into t2 values
('foo'),('bar'),('boo'),('car'),('coo'),('par'),('doo'),('tar');
explain select t1.* from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL PRIMARY 10 NULL 2 Using index
1 SIMPLE t2 ref a a 3 test.t1.a 2 Using where
drop table t1, t2;
#
# check UPDATE/DELETE that look like they could be eliminated
#
create table t1 (a int primary key, b int);
insert into t1 values (1,1),(2,2),(3,3);
create table t2 like t1;
insert into t2 select * from t1;
update t1 left join t2 using (a) set t2.a=t2.a+100;
select * from t1;
a b
1 1
2 2
3 3
select * from t2;
a b
101 1
102 2
103 3
delete from t2;
insert into t2 select * from t1;
delete t2 from t1 left join t2 using (a);
select * from t1;
a b
1 1
2 2
3 3
select * from t2;
a b
drop table t1, t2;
#
# Tests with various edge-case ON expressions
#
create table t1 (a int, b int, c int, d int);
insert into t1 values (0,0,0,0),(1,1,1,1),(2,2,2,2),(3,3,3,3);
create table t2 (pk int primary key, b int)
as select a as pk, a as b from t1 where a in (1,2);
create table t3 (pk1 int, pk2 int, b int, unique(pk1,pk2));
insert into t3 select a as pk1, a as pk2, a as b from t1 where a in (1,3);
explain select t1.a from t1 left join t2 on t2.pk=t1.a and t2.b<t1.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain select t1.a from t1 left join t2 on t2.pk=t1.a or t2.b<t1.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 2 Using where
explain select t1.a from t1 left join t2 on t2.b<t1.b or t2.pk=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 2 Using where
explain select t1.a from t1 left join t2 on t2.pk between 10 and 20;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 index PRIMARY PRIMARY 4 NULL 2 Using where; Using index
explain select t1.a from t1 left join t2 on t2.pk between 0.5 and 1.5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 index PRIMARY PRIMARY 4 NULL 2 Using where; Using index
explain select t1.a from t1 left join t2 on t2.pk between 10 and 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain select t1.a from t1 left join t2 on t2.pk in (10);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain select t1.a from t1 left join t2 on t2.pk in (t1.a);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain select t1.a from t1 left join t2 on TRUE;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 index NULL PRIMARY 4 NULL 2 Using where; Using index
explain select t1.a from t1 left join t3 on t3.pk1=t1.a and t3.pk2 IS NULL;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
drop table t1,t2,t3;
#
# Multi-equality tests
#
create table t1 (a int, b int, c int, d int);
insert into t1 values (0,0,0,0),(1,1,1,1),(2,2,2,2),(3,3,3,3);
create table t2 (pk int primary key, b int, c int);
insert into t2 select a,a,a from t1 where a in (1,2);
explain
select t1.*
from t1 left join t2 on t2.pk=t2.c and t2.b=t1.a and t1.a=t1.b and t2.c=t2.b
where t1.d=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using where
explain
select t1.*
from
t1
left join
t2
on (t2.pk=t2.c and t2.b=t1.a and t1.a=t1.b and t2.c=t2.b) or
(t2.pk=t2.c and t2.b=t1.a and t1.a=t1.b and t2.c=t2.b)
where t1.d=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using where
#This can't be eliminated:
explain
select t1.*
from
t1
left join
t2
on (t2.pk=t2.c and t2.b=t1.a and t2.c=t1.b) or
(t2.pk=t2.c and t1.a=t1.b and t2.c=t1.b)
where t1.d=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using where
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.b 1 Using where
explain
select t1.*
from
t1
left join
t2
on (t2.pk=t2.c and t2.b=t1.a and t2.c=t1.b) or
(t2.pk=t2.c and t2.c=t1.b)
;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain
select t1.*
from t1 left join t2 on t2.pk=3 or t2.pk= 4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 index PRIMARY PRIMARY 4 NULL 2 Using where; Using index
explain
select t1.*
from t1 left join t2 on t2.pk=3 or t2.pk= 3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
explain
select t1.*
from t1 left join t2 on (t2.pk=3 and t2.b=3) or (t2.pk= 4 and t2.b=3);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 2 Using where
drop table t1, t2;
#
# LPBUG#523593: Running RQG optimizer_no_subquery crashes MariaDB
#
CREATE TABLE t1 (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`col_int_nokey` int(11) DEFAULT NULL,
`col_int_key` int(11) DEFAULT NULL,
`col_date_key` date DEFAULT NULL,
`col_date_nokey` date DEFAULT NULL,
`col_time_key` time DEFAULT NULL,
`col_time_nokey` time DEFAULT NULL,
`col_datetime_key` datetime DEFAULT NULL,
`col_datetime_nokey` datetime DEFAULT NULL,
`col_varchar_key` varchar(1) DEFAULT NULL,
`col_varchar_nokey` varchar(1) DEFAULT NULL,
PRIMARY KEY (`pk`),
KEY `col_int_key` (`col_int_key`),
KEY `col_date_key` (`col_date_key`),
KEY `col_time_key` (`col_time_key`),
KEY `col_datetime_key` (`col_datetime_key`),
KEY `col_varchar_key` (`col_varchar_key`,`col_int_key`)
);
CREATE TABLE t2 LIKE t1;
INSERT INTO t1 VALUES
(10,7,8,NULL,NULL,'01:27:35','01:27:35','2002-02-26 06:14:37','2002-02-26 06:14:37','v','v'),
(11,1,9,'2006-06-14','2006-06-14','19:48:31','19:48:31','1900-01-01 00:00:00','1900-01-01 00:00:00','r','r');
INSERT INTO t2 SELECT * FROM t1;
SELECT table2.col_int_key AS field1
FROM (
t2 AS table1
RIGHT OUTER JOIN
(
( t1 AS table2 STRAIGHT_JOIN
t1 AS table3 ON (
(table3.col_varchar_nokey = table2.col_varchar_key ) AND
(table3.pk = table2.col_int_key))
)
) ON
(
(table3.col_varchar_key = table2.col_varchar_key) OR
(table3.col_int_key = table2.pk)
)
)
HAVING field1 < 216;
field1
DROP TABLE t1, t2;
#
# LPBUG#524025 Running RQG outer_join test leads to crash
#
CREATE TABLE t0 (
pk int(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (pk)
);
CREATE TABLE t1 (
col_int int(11) DEFAULT NULL,
col_int_key int(11) DEFAULT NULL,
pk int(11) NOT NULL AUTO_INCREMENT,
col_varchar_10_latin1 varchar(10) DEFAULT NULL,
PRIMARY KEY (pk)
);
INSERT INTO t1 VALUES (5,5,1,'t'), (NULL,NULL,2,'y');
CREATE TABLE t2 (
col_int int(11) DEFAULT NULL
);
INSERT INTO t2 VALUES (8), (4);
CREATE TABLE t3 (
pk int(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (pk)
);
INSERT INTO t3 VALUES (1),(8);
CREATE TABLE t4 (
pk int(11) NOT NULL AUTO_INCREMENT,
col_varchar_1024_latin1_key varchar(1024) DEFAULT NULL,
col_int int(11) DEFAULT NULL,
PRIMARY KEY (pk)
);
INSERT INTO t4 VALUES (1,'o',1), (2,'w',2);
CREATE TABLE t5 (
col_varchar_1024_utf8_key varchar(1024) CHARACTER SET utf8 DEFAULT NULL,
col_varchar_1024_latin1_key varchar(1024) DEFAULT NULL,
col_varchar_10_utf8_key varchar(1024) CHARACTER SET utf8 DEFAULT NULL,
pk int(11) NOT NULL AUTO_INCREMENT,
col_int_key int(11) DEFAULT NULL,
PRIMARY KEY (pk)
);
INSERT INTO t5 VALUES ('k','a','z',1,2),('x','a','w',2,7);
CREATE TABLE t6 (
col_int int(11) DEFAULT NULL,
col_int_key int(11) DEFAULT NULL
);
INSERT INTO t6 VALUES (6,1),(8,3);
SELECT
table3.col_int AS field1,
table1.col_int AS field2,
table1.col_int_key AS field3,
table1.pk AS field4,
table1.col_int AS field5,
table2.col_int AS field6
FROM
t1 AS table1
LEFT OUTER JOIN
t4 AS table2
LEFT JOIN t6 AS table3
RIGHT JOIN t3 AS table4
LEFT JOIN t5 AS table5 ON table4.pk = table5.pk
LEFT JOIN t0 AS table6 ON table5.col_int_key = table6.pk
ON table3.col_int_key = table5.pk
ON table2.col_varchar_1024_latin1_key = table5.col_varchar_10_utf8_key
LEFT JOIN t6 AS table7 ON table2.pk = table7.col_int
ON table1.col_varchar_10_latin1 = table5.col_varchar_1024_latin1_key
LEFT JOIN t2 AS table8 ON table3.col_int = table8.col_int
WHERE
table1.col_int_key < table2.pk
HAVING
field4 != 6;
field1 field2 field3 field4 field5 field6
drop table t0,t1,t2,t3,t4,t5,t6;
#
# BUG#675118: Elimination of a table results in an invalid execution plan
#
CREATE TABLE t1 (f1 int(11), PRIMARY KEY (f1)) ;
CREATE TABLE t2 (f4 varchar(1024), KEY (f4)) ;
Warnings:
Warning 1071 Specified key was too long; max key length is 1000 bytes
INSERT IGNORE INTO t2 VALUES ('xcddwntkbxyorzdv'),
('cnxxcddwntkbxyor'),('r'),('r'), ('did'),('I'),('when'),
('hczkfqjeggivdvac'),('e'),('okay'),('up');
CREATE TABLE t3 (f4 varchar(1024), f1 int(11), f2 int(11)) ;
INSERT IGNORE INTO t3 VALUES ('f','4','0'),('n','5','-996540416');
CREATE TABLE t4 (f1 int(11), f3 varchar(10)) ;
INSERT IGNORE INTO t4 VALUES ('8','n'),('9','nwzcerzsgx'),('10','c');
CREATE TABLE t5 (f5 int(11), KEY (f5)) ;
EXPLAIN
SELECT t3.f2
FROM t2
LEFT JOIN t3
LEFT JOIN t4
LEFT JOIN t1 ON t4.f1 = t1.f1
JOIN t5 ON t4.f3 ON t3.f1 = t5.f5 ON t2.f4 = t3.f4
WHERE t3.f2 ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 Using where
1 SIMPLE t5 ref f5 f5 5 test.t3.f1 2 Using where; Using index
1 SIMPLE t4 ALL NULL NULL NULL NULL 3 Using where
1 SIMPLE t2 ALL f4 NULL NULL NULL 11 Using where; Using join buffer (flat, BNL join)
# ^^ The above must not produce a QEP of t3,t5,t2,t4
# as that violates the "no interleaving of outer join nests" rule.
DROP TABLE t1,t2,t3,t4,t5;
#
# BUG#997747: Assertion `join->best_read < ((double)1.79..5e+308L)'
# failed in greedy_search with LEFT JOINs and unique keys
#
CREATE TABLE t1 (a1 INT);
CREATE TABLE t2 (b1 INT);
CREATE TABLE t3 (c1 INT, UNIQUE KEY(c1));
CREATE TABLE t4 (d1 INT, UNIQUE KEY(d1));
CREATE TABLE t5 (e1 INT);
INSERT INTO t1 VALUES (1),(2);
INSERT INTO t2 VALUES (2),(3);
INSERT INTO t3 VALUES (3),(4);
INSERT INTO t4 VALUES (4),(5);
INSERT INTO t5 VALUES (5),(6);
SELECT a1 FROM t1 LEFT JOIN t2 LEFT JOIN t3 LEFT JOIN t4
ON c1 = d1 ON d1 = b1 ON a1 = b1
LEFT JOIN t5 ON a1 = e1 ;
a1
1
2
DROP TABLE t1,t2,t3,t4,t5;
#
# BUG#884184: Wrong result with RIGHT JOIN + derived_merge
#
CREATE TABLE t1 (a int(11), b varchar(1)) ;
INSERT IGNORE INTO t1 VALUES (0,'g');
CREATE TABLE t3 ( a varchar(1)) ;
INSERT IGNORE INTO t3 VALUES ('g');
CREATE TABLE t2 ( a int(11) NOT NULL, PRIMARY KEY (a));
INSERT INTO t2 VALUES (9), (10);
create view v1 as SELECT t1.* FROM t1 LEFT JOIN t2 ON ( t1.a = t2.a ) WHERE t2.a <> 0;
SELECT alias1.* FROM t3 LEFT JOIN v1 as alias1 ON ( t3.a = alias1.b );
a b
NULL NULL
EXPLAIN SELECT alias1.* FROM t3 LEFT JOIN v1 as alias1 ON ( t3.a = alias1.b );
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t3 system NULL NULL NULL NULL 1
1 SIMPLE t1 ALL NULL NULL NULL NULL 1 Using where
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using index
drop view v1;
DROP TABLE t1,t2,t3;
#
# MDEV-5344: LEFT OUTER JOIN table data is lost in ON DUPLICATE KEY UPDATE section
#
create table t1 (
id int(10) unsigned NOT NULL DEFAULT '0',
v int(10) unsigned DEFAULT '0',
PRIMARY KEY (id)
);
create table t2 (
id int(10) unsigned NOT NULL DEFAULT '0',
PRIMARY KEY (id)
) ;
create table t3 (
id int(10) unsigned NOT NULL DEFAULT '0',
v int(10) unsigned DEFAULT '0',
PRIMARY KEY (id)
);
insert into t1 values (1, 10), (2, 10);
insert into t2 values (1), (2);
insert into t3 values (1, 20);
insert into t1
select t2.id, 5 from t2 LEFT OUTER JOIN t3 ON t2.id = t3.id
on duplicate key update t1.v = t3.v;
select * from t1;
id v
1 20
2 NULL
drop table t1,t2,t3;
#
# BUG#919878: Assertion `!eliminated_tables...
#
CREATE TABLE t1 ( a INT );
INSERT INTO t1 VALUES (1);
CREATE TABLE t2
( b INT, UNIQUE INDEX(b) );
INSERT INTO t2 VALUES (1),(2);
EXPLAIN EXTENDED
SELECT * FROM t2
WHERE b IN (
SELECT SUM(a) FROM t1 LEFT JOIN t2 ON b=a
);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 index NULL b 5 NULL 2 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 system NULL NULL NULL NULL 1 100.00
Warnings:
Note 1003 select `test`.`t2`.`b` AS `b` from `test`.`t2` where <expr_cache><`test`.`t2`.`b`>(<in_optimizer>(`test`.`t2`.`b`,<exists>(select sum(1) from dual where 1 having (<cache>(`test`.`t2`.`b`) = <ref_null_helper>(sum(1))))))
DROP TABLE t1,t2;
#
# MDEV-4840: Wrong result (missing rows) on LEFT JOIN with InnoDB tables
#
CREATE TABLE t1 (alpha3 VARCHAR(3));
INSERT INTO t1 VALUES ('USA'),('CAN');
CREATE TABLE t2 ( t3_code VARCHAR(3), name VARCHAR(64));
INSERT INTO t2 VALUES ('USA','Austin'),('USA','Boston');
CREATE TABLE t3 ( code VARCHAR(3), name VARCHAR(64), PRIMARY KEY (code), UNIQUE KEY (name));
INSERT INTO t3 VALUES ('CAN','Canada'),('USA','United States');
SELECT * FROM t1 LEFT JOIN ( t2 LEFT JOIN t3 ON t2.t3_code = t3.code ) ON t1.alpha3 = t3.code;
alpha3 t3_code name code name
USA USA Austin USA United States
USA USA Boston USA United States
CAN NULL NULL NULL NULL
SELECT t1.alpha3 FROM t1 LEFT JOIN ( t2 LEFT JOIN t3 ON t2.t3_code = t3.code ) ON t1.alpha3 = t3.code;
alpha3
USA
USA
CAN
DROP TABLE t1, t2, t3;
SET optimizer_switch=@save_optimizer_switch;
#
# MDEV-7893: table_elimination works wrong with on computed expression and compound unique key
# (just a testcase)
CREATE TABLE t1 (
PostID int(10) unsigned NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Warnings:
Warning 1286 Unknown storage engine 'InnoDB'
Warning 1266 Using storage engine MyISAM for table 't1'
INSERT INTO t1 (PostID) VALUES (1), (2);
CREATE TABLE t2 (
VoteID int(10) unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,
EntityID int(10) unsigned NOT NULL,
UserID int(10) unsigned NOT NULL,
UNIQUE KEY EntityID (EntityID,UserID)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Warnings:
Warning 1286 Unknown storage engine 'InnoDB'
Warning 1266 Using storage engine MyISAM for table 't2'
INSERT INTO t2 (EntityID, UserID) VALUES (1, 30), (2, 30);
SELECT t1.*, T.Voted as Voted
FROM
t1 LEFT JOIN (
SELECT 1 AS Voted, EntityID
FROM t2
WHERE t2.UserID = '20' ) AS T
ON T.EntityID = t1.PostID
WHERE t1.PostID='1'
LIMIT 1;
PostID Voted
1 NULL
DROP TABLE t1,t2;
|