drop table if exists t1,t2,t3,t4; drop view if exists v1,v2,v3; set @subselect_extra_tmp=@@optimizer_switch; set @@optimizer_switch=ifnull(@optimizer_switch_for_subselect_extra_test, "semijoin=on,firstmatch=on,loosescan=on,semijoin_with_cache=on,partial_match_rowid_merge=off,partial_match_table_scan=off"); # From explain.test: # # Bug#37870: Usage of uninitialized value caused failed assertion. # create table t1 (dt datetime not null, t time not null); create table t2 (dt datetime not null); insert into t1 values ('2001-01-01 1:1:1', '1:1:1'), ('2001-01-01 1:1:1', '1:1:1'); insert into t2 values ('2001-01-01 1:1:1'), ('2001-01-01 1:1:1'); flush tables; EXPLAIN SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN (SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.dt IS NULL ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY OUTR ALL NULL NULL NULL NULL 2 Using where 1 PRIMARY INNR ALL NULL NULL NULL NULL 2 Using where; FirstMatch(OUTR); Using join buffer (flat, BNL join) flush tables; SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN (SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.dt IS NULL ); dt flush tables; EXPLAIN SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN ( SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.t < '2005-11-13 7:41:31' ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY OUTR ALL NULL NULL NULL NULL 2 Using where 1 PRIMARY INNR ALL NULL NULL NULL NULL 2 Using where; FirstMatch(OUTR); Using join buffer (flat, BNL join) flush tables; SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN ( SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.t < '2005-11-13 7:41:31' ); dt 2001-01-01 01:01:01 2001-01-01 01:01:01 drop tables t1, t2; # From type_datetime.test: # # Bug #32694: NOT NULL table field in a subquery produces invalid results # create table t1 (id int(10) not null, cur_date datetime not null); create table t2 (id int(10) not null, cur_date date not null); insert into t1 (id, cur_date) values (1, '2007-04-25 18:30:22'); insert into t2 (id, cur_date) values (1, '2007-04-25'); explain extended select * from t1 where id in (select id from t1 as x1 where (t1.cur_date is null)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables Warnings: Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1 Note 1003 select 1 AS `id`,'2007-04-25 18:30:22' AS `cur_date` from (dual) where 0 select * from t1 where id in (select id from t1 as x1 where (t1.cur_date is null)); id cur_date explain extended select * from t2 where id in (select id from t2 as x1 where (t2.cur_date is null)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables Warnings: Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1 Note 1003 select 1 AS `id`,'2007-04-25' AS `cur_date` from (dual) where 0 select * from t2 where id in (select id from t2 as x1 where (t2.cur_date is null)); id cur_date insert into t1 (id, cur_date) values (2, '2007-04-26 18:30:22'); insert into t2 (id, cur_date) values (2, '2007-04-26'); explain extended select * from t1 where id in (select id from t1 as x1 where (t1.cur_date is null)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 2 100.00 Using where 1 PRIMARY x1 ALL NULL NULL NULL NULL 2 50.00 Using where; FirstMatch(t1); Using join buffer (flat, BNL join) Warnings: Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1 Note 1003 select `test`.`t1`.`id` AS `id`,`test`.`t1`.`cur_date` AS `cur_date` from `test`.`t1` semi join (`test`.`t1` `x1`) where `test`.`x1`.`id` = `test`.`t1`.`id` and `test`.`t1`.`cur_date` = 0 select * from t1 where id in (select id from t1 as x1 where (t1.cur_date is null)); id cur_date explain extended select * from t2 where id in (select id from t2 as x1 where (t2.cur_date is null)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where 1 PRIMARY x1 ALL NULL NULL NULL NULL 2 50.00 Using where; FirstMatch(t2); Using join buffer (flat, BNL join) Warnings: Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1 Note 1003 select `test`.`t2`.`id` AS `id`,`test`.`t2`.`cur_date` AS `cur_date` from `test`.`t2` semi join (`test`.`t2` `x1`) where `test`.`x1`.`id` = `test`.`t2`.`id` and `test`.`t2`.`cur_date` = 0 select * from t2 where id in (select id from t2 as x1 where (t2.cur_date is null)); id cur_date drop table t1,t2; # # From group_min_max.test # create table t1 ( a1 char(64), a2 char(64), b char(16), c char(16) not null, d char(16), dummy char(64) default ' ' ); insert into t1 (a1, a2, b, c, d) values ('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'), ('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'), ('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'), ('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'), ('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'), ('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'), ('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'), ('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'), ('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'), ('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'), ('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'), ('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'), ('d','a','a','a411','xy1'),('d','a','a','b411','xy2'),('d','a','a','c411','xy3'),('d','a','a','d411','xy4'), ('d','a','b','e412','xy1'),('d','a','b','f412','xy2'),('d','a','b','g412','xy3'),('d','a','b','h412','xy4'), ('d','b','a','i421','xy1'),('d','b','a','j421','xy2'),('d','b','a','k421','xy3'),('d','b','a','l421','xy4'), ('d','b','b','m422','xy1'),('d','b','b','n422','xy2'),('d','b','b','o422','xy3'),('d','b','b','p422','xy4'), ('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'), ('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'), ('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'), ('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'), ('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'), ('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'), ('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'), ('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'), ('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'), ('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'), ('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'), ('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'), ('d','a','a','a411','xy1'),('d','a','a','b411','xy2'),('d','a','a','c411','xy3'),('d','a','a','d411','xy4'), ('d','a','b','e412','xy1'),('d','a','b','f412','xy2'),('d','a','b','g412','xy3'),('d','a','b','h412','xy4'), ('d','b','a','i421','xy1'),('d','b','a','j421','xy2'),('d','b','a','k421','xy3'),('d','b','a','l421','xy4'), ('d','b','b','m422','xy1'),('d','b','b','n422','xy2'),('d','b','b','o422','xy3'),('d','b','b','p422','xy4'); create index idx_t1_0 on t1 (a1); create index idx_t1_1 on t1 (a1,a2,b,c); create index idx_t1_2 on t1 (a1,a2,b); analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status Table is already up to date create table t2 ( a1 char(64), a2 char(64) not null, b char(16), c char(16), d char(16), dummy char(64) default ' ' ); insert into t2 select * from t1; insert into t2 (a1, a2, b, c, d) values ('a','a',NULL,'a777','xyz'),('a','a',NULL,'a888','xyz'),('a','a',NULL,'a999','xyz'), ('a','a','a',NULL,'xyz'), ('a','a','b',NULL,'xyz'), ('a','b','a',NULL,'xyz'), ('c','a',NULL,'c777','xyz'),('c','a',NULL,'c888','xyz'),('c','a',NULL,'c999','xyz'), ('d','b','b',NULL,'xyz'), ('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'), ('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'), ('a','a',NULL,'a777','xyz'),('a','a',NULL,'a888','xyz'),('a','a',NULL,'a999','xyz'), ('a','a','a',NULL,'xyz'), ('a','a','b',NULL,'xyz'), ('a','b','a',NULL,'xyz'), ('c','a',NULL,'c777','xyz'),('c','a',NULL,'c888','xyz'),('c','a',NULL,'c999','xyz'), ('d','b','b',NULL,'xyz'), ('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'), ('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'); create index idx_t2_0 on t2 (a1); create index idx_t2_1 on t2 (a1,a2,b,c); create index idx_t2_2 on t2 (a1,a2,b); analyze table t2; Table Op Msg_type Msg_text test.t2 analyze status Engine-independent statistics collected test.t2 analyze status Table is already up to date create table t3 ( a1 char(1), a2 char(1), b char(1), c char(4) not null, d char(3), dummy char(1) default ' ' ); insert into t3 (a1, a2, b, c, d) values ('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'), ('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'), ('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'), ('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'), ('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'), ('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'), ('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'), ('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'), ('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'), ('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'), ('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'), ('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'); insert into t3 (a1, a2, b, c, d) values ('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'), ('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'), ('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'), ('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'), ('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'), ('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'), ('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'), ('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'), ('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'), ('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'), ('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'), ('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'); insert into t3 (a1, a2, b, c, d) values ('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'), ('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'), ('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'), ('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'), ('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'), ('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'), ('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'), ('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'), ('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'), ('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'), ('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'), ('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'); insert into t3 (a1, a2, b, c, d) values ('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'), ('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'), ('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'), ('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'), ('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'), ('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'), ('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'), ('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'), ('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'), ('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'), ('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'), ('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'); create index idx_t3_0 on t3 (a1); create index idx_t3_1 on t3 (a1,a2,b,c); create index idx_t3_2 on t3 (a1,a2,b); analyze table t3; Table Op Msg_type Msg_text test.t3 analyze status Engine-independent statistics collected test.t3 analyze status Table is already up to date explain select a1,a2,b,c,min(c), max(c) from t1 where exists ( select * from t2 where t2.c in (select c from t3 where t3.c > t1.b) and t2.c > 'b1' ) group by a1,a2,b; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 index NULL idx_t1_1 163 NULL 128 Using where; Using index 2 DEPENDENT SUBQUERY t2 index NULL idx_t2_1 163 NULL 164 Using where; Using index 2 DEPENDENT SUBQUERY t3 index NULL idx_t3_1 10 NULL 192 Using where; Using index; FirstMatch(t2); Using join buffer (flat, BNL join) select a1,a2,b,c,min(c), max(c) from t1 where exists ( select * from t2 where t2.c in (select c from t3 where t3.c > t1.b) and t2.c > 'b1' ) group by a1,a2,b; a1 a2 b c min(c) max(c) a a a a111 a111 d111 a a b e112 e112 h112 a b a i121 i121 l121 a b b m122 m122 p122 b a a a211 a211 d211 b a b e212 e212 h212 b b a i221 i221 l221 b b b m222 m222 p222 c a a a311 a311 d311 c a b e312 e312 h312 c b a i321 i321 l321 c b b m322 m322 p322 d a a a411 a411 d411 d a b e412 e412 h412 d b a i421 i421 l421 d b b m422 m422 p422 explain select a1,a2,b,c,min(c), max(c) from t1 where exists ( select * from t2 where t2.c in (select c from t3 where t3.c > t1.c) and t2.c > 'b1' ) group by a1,a2,b; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 index NULL idx_t1_1 163 NULL 128 Using where; Using index 2 DEPENDENT SUBQUERY t2 index NULL idx_t2_1 163 NULL 164 Using where; Using index 2 DEPENDENT SUBQUERY t3 index NULL idx_t3_1 10 NULL 192 Using where; Using index; FirstMatch(t2); Using join buffer (flat, BNL join) select a1,a2,b,c,min(c), max(c) from t1 where exists ( select * from t2 where t2.c in (select c from t3 where t3.c > t1.c) and t2.c > 'b1' ) group by a1,a2,b; a1 a2 b c min(c) max(c) a a a a111 a111 d111 a a b e112 e112 h112 a b a i121 i121 l121 a b b m122 m122 p122 b a a a211 a211 d211 b a b e212 e212 h212 b b a i221 i221 l221 b b b m222 m222 p222 c a a a311 a311 d311 c a b e312 e312 h312 c b a i321 i321 l321 c b b m322 m322 o322 d a a a411 a411 d411 d a b e412 e412 h412 d b a i421 i421 l421 d b b m422 m422 o422 drop table t1, t2, t3; # # From group_by.test # # Bug #21174: Index degrades sort performance and # optimizer does not honor IGNORE INDEX. # a.k.a WL3527. # CREATE TABLE t1 (a INT, b INT, PRIMARY KEY (a), KEY i2(a,b)); INSERT INTO t1 VALUES (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8); INSERT INTO t1 SELECT a + 8,b FROM t1; INSERT INTO t1 SELECT a + 16,b FROM t1; INSERT INTO t1 SELECT a + 32,b FROM t1; INSERT INTO t1 SELECT a + 64,b FROM t1; INSERT INTO t1 SELECT a + 128,b FROM t1 limit 16; ANALYZE TABLE t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK EXPLAIN SELECT 1 FROM t1 WHERE a IN (SELECT a FROM t1 USE INDEX (i2) IGNORE INDEX (i2)); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 index PRIMARY,i2 PRIMARY 4 NULL 144 Using index 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED t1 ALL NULL NULL NULL NULL 144 CREATE TABLE t2 (a INT, b INT, KEY(a)); INSERT INTO t2 VALUES (1, 1), (2, 2), (3,3), (4,4); EXPLAIN SELECT a, SUM(b) FROM t2 GROUP BY a LIMIT 2; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 index NULL a 5 NULL 2 EXPLAIN SELECT a, SUM(b) FROM t2 IGNORE INDEX (a) GROUP BY a LIMIT 2; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort EXPLAIN SELECT 1 FROM t2 WHERE a IN (SELECT a FROM t1 USE INDEX (i2) IGNORE INDEX (i2)); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 index a a 5 NULL 4 Using index 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED t1 ALL NULL NULL NULL NULL 144 DROP TABLE t1, t2; # # From derived_view.test # set @tmp_subselect_extra_derived=@@optimizer_switch; set optimizer_switch='derived_merge=on,derived_with_keys=on'; # # LP bug #806504: right join over a view/derived table # CREATE TABLE t1 (a int, b int) ; INSERT INTO t1 VALUES (0,0); CREATE TABLE t2 (a int) ; INSERT INTO t2 VALUES (0), (0); CREATE VIEW v1 AS SELECT * FROM t1; SELECT * FROM t2 RIGHT JOIN (SELECT * FROM t1) AS t ON t.a != 0 WHERE t.a IN (SELECT b FROM t1); a a b NULL 0 0 EXPLAIN EXTENDED SELECT * FROM t2 RIGHT JOIN (SELECT * FROM t1) AS t ON t.a != 0 WHERE t.a IN (SELECT b FROM t1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00 1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00 1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where Warnings: Note 1003 select `test`.`t2`.`a` AS `a`,0 AS `a`,0 AS `b` from `test`.`t2` semi join (dual) where 1 SELECT * FROM t2 RIGHT JOIN v1 AS t ON t.a != 0 WHERE t.a IN (SELECT b FROM t1); a a b NULL 0 0 EXPLAIN EXTENDED SELECT * FROM t2 RIGHT JOIN v1 AS t ON t.a != 0 WHERE t.a IN (SELECT b FROM t1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00 1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00 1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where Warnings: Note 1003 select `test`.`t2`.`a` AS `a`,0 AS `a`,0 AS `b` from `test`.`t2` semi join (dual) where 1 DROP VIEW v1; DROP TABLE t1,t2; # # LP bug #793448: materialized view accessed by two-component key # CREATE TABLE t1 (a int, b int); INSERT INTO t1 VALUES (9,3), (2,5); CREATE TABLE t2 (a int, b int); INSERT INTO t2 VALUES (9,3), (3,7), (9,1), (2,5), (2,4), (3,8); CREATE TABLE t3 (a int, b int); INSERT INTO t3 VALUES (10,3), (9,7), (9,1), (2,4); CREATE VIEW v1(a,b) AS SELECT a, MAX(b) FROM t2 GROUP BY a; CREATE VIEW v2(a,b) AS SELECT a,b FROM t2 UNION SELECT a,b FROM t3; SELECT * FROM v1; a b 2 5 3 8 9 3 SELECT a FROM t1 WHERE (a,b) IN (SELECT * FROM v1); a 9 2 EXPLAIN SELECT a FROM t1 WHERE (a,b) IN (SELECT * FROM v1); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where 1 PRIMARY ref key0 key0 10 test.t1.a,test.t1.b 1 FirstMatch(t1) 3 DERIVED t2 ALL NULL NULL NULL NULL 6 Using temporary; Using filesort SELECT * FROM v2; a b 9 3 3 7 9 1 2 5 2 4 3 8 10 3 9 7 SELECT a FROM t1 WHERE (a,b) IN (SELECT * FROM v2); a 9 2 EXPLAIN SELECT a FROM t1 WHERE (a,b) IN (SELECT * FROM v2); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where 1 PRIMARY eq_ref distinct_key distinct_key 10 test.t1.a,test.t1.b 1 3 DERIVED t2 ALL NULL NULL NULL NULL 6 4 UNION t3 ALL NULL NULL NULL NULL 4 NULL UNION RESULT ALL NULL NULL NULL NULL NULL DROP VIEW v1,v2; DROP TABLE t1,t2,t3; # # LP bug #874006: materialized view used in IN subquery # CREATE TABLE t3 (a int NOT NULL, b varchar(1), c varchar(1)); INSERT INTO t3 VALUES (19,NULL,NULL), (20,'r','r'); CREATE TABLE t1 (a int, b varchar(1) , c varchar(1)); INSERT INTO t1 VALUES (1,NULL,NULL), (5,'r','r'), (7,'y','y'); CREATE TABLE t2 (a int NOT NULL , b int, c varchar(1)); INSERT INTO t2 VALUES (4,3,'r'); CREATE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT * FROM t1; SET SESSION optimizer_switch='derived_with_keys=off'; EXPLAIN SELECT * FROM t3 WHERE t3.b IN (SELECT v1.b FROM v1, t2 WHERE t2.c = v1.c AND t2.c = v1.b AND v1.b = t3.c); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 system NULL NULL NULL NULL 1 1 PRIMARY t3 ALL NULL NULL NULL NULL 2 Using where 1 PRIMARY ALL NULL NULL NULL NULL 3 Using where; FirstMatch(t3); Using join buffer (flat, BNL join) 3 DERIVED t1 ALL NULL NULL NULL NULL 3 Using where SELECT * FROM t3 WHERE t3.b IN (SELECT v1.b FROM v1, t2 WHERE t2.c = v1.c AND t2.c = v1.b AND v1.b = t3.c); a b c 20 r r SET SESSION optimizer_switch='derived_with_keys=on'; EXPLAIN SELECT * FROM t3 WHERE t3.b IN (SELECT v1.b FROM v1, t2 WHERE t2.c = v1.c AND t2.c = v1.b AND v1.b = t3.c); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 system NULL NULL NULL NULL 1 1 PRIMARY t3 ALL NULL NULL NULL NULL 2 Using where 1 PRIMARY ref key1 key1 8 const,const 0 FirstMatch(t3) 3 DERIVED t1 ALL NULL NULL NULL NULL 3 Using where SELECT * FROM t3 WHERE t3.b IN (SELECT v1.b FROM v1, t2 WHERE t2.c = v1.c AND t2.c = v1.b AND v1.b = t3.c); a b c 20 r r DROP VIEW v1; DROP TABLE t1,t2,t3; # # LP bug #873263: materialized view used in correlated IN subquery # CREATE TABLE t1 (a int, b int) ; INSERT INTO t1 VALUES (5,4), (9,8); CREATE TABLE t2 (a int, b int) ; INSERT INTO t2 VALUES (4,5), (5,1); CREATE ALGORITHM=TEMPTABLE VIEW v2 AS SELECT * FROM t2; SET SESSION optimizer_switch='derived_with_keys=on'; EXPLAIN SELECT * FROM t1 WHERE t1.b IN (SELECT v2.a FROM v2 WHERE v2.b = t1.a); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where 1 PRIMARY ref key0 key0 10 test.t1.b,test.t1.a 1 FirstMatch(t1) 3 DERIVED t2 ALL NULL NULL NULL NULL 2 SELECT * FROM t1 WHERE t1.b IN (SELECT v2.a FROM v2 WHERE v2.b = t1.a); a b 5 4 DROP VIEW v2; DROP TABLE t1,t2; set optimizer_switch= @tmp_subselect_extra_derived;