set @save_optimizer_switch_jcl6=@@optimizer_switch; set @@optimizer_switch='optimize_join_buffer_size=on'; set @@optimizer_switch='semijoin_with_cache=on'; set @@optimizer_switch='outer_join_with_cache=on'; set optimizer_switch='mrr=on,mrr_sort_keys=on,index_condition_pushdown=on'; set join_cache_level=6; show variables like 'join_cache_level'; Variable_name Value join_cache_level 6 set @optimizer_switch_for_subselect_sj2_test=@@optimizer_switch; set @join_cache_level_for_subselect_sj2_test=@@join_cache_level; set @subselect_sj2_tmp= @@optimizer_switch; set optimizer_switch='semijoin=on,firstmatch=on,loosescan=on'; set optimizer_switch='mrr=on,mrr_sort_keys=on,index_condition_pushdown=on'; SET optimizer_switch=ifnull(@optimizer_switch_for_subselect_sj2_test,'outer_join_with_cache=off'); SET optimizer_switch=ifnull(@optimizer_switch_for_subselect_sj2_test,'semijoin_with_cache=off'); set join_cache_level=@join_cache_level_for_subselect_sj2_test; drop table if exists t0, t1, t2, t3, t4, t5; drop view if exists v1; create table t0 (a int); insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); create table t1 ( a int, b int ); insert into t1 values (1,1),(1,1),(2,2); create table t2 ( a int, b int, key(b) ); insert into t2 select a, a/2 from t0; insert into t2 select a+10, a+10/2 from t0; select * from t1; a b 1 1 1 1 2 2 select * from t2; a b 0 0 1 1 2 1 3 2 4 2 5 3 6 3 7 4 8 4 9 5 10 5 11 6 12 7 13 8 14 9 15 10 16 11 17 12 18 13 19 14 explain select * from t2 where b in (select a from t1); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 ALL b NULL NULL NULL 20 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED t1 ALL NULL NULL NULL NULL 3 select * from t2 where b in (select a from t1); a b 1 1 2 1 3 2 4 2 create table t3 ( a int, b int, key(b), pk1 char(200), pk2 char(200), pk3 char(200), primary key(pk1, pk2, pk3) ) engine=innodb; insert into t3 select a,a, a,a,a from t0; insert into t3 select a,a, a+100,a+100,a+100 from t0; explain select * from t3 where b in (select a from t1); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL b NULL NULL NULL 20 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED t1 ALL NULL NULL NULL NULL 3 select * from t3 where b in (select a from t1); a b pk1 pk2 pk3 1 1 1 1 1 1 1 101 101 101 2 2 102 102 102 2 2 2 2 2 set @save_max_heap_table_size= @@max_heap_table_size; set max_heap_table_size=16384; set @save_join_buffer_size = @@join_buffer_size; set join_buffer_size= 8192; drop table t3; create table t3 ( a int, b int, key(b), pk1 char(200), pk2 char(200), primary key(pk1, pk2) ) engine=innodb; insert into t3 select A.a + 10*B.a, A.a + 10*B.a, A.a + 10*B.a, A.a + 10*B.a from t0 A, t0 B where B.a <5; explain select * from t3 where b in (select a from t0); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL b NULL NULL NULL # 1 PRIMARY eq_ref distinct_key distinct_key 4 func # 2 MATERIALIZED t0 ALL NULL NULL NULL NULL # select * from t3 where b in (select A.a+B.a from t0 A, t0 B where B.a<5); a b pk1 pk2 0 0 0 0 1 1 1 1 10 10 10 10 11 11 11 11 12 12 12 12 13 13 13 13 2 2 2 2 3 3 3 3 4 4 4 4 5 5 5 5 6 6 6 6 7 7 7 7 8 8 8 8 9 9 9 9 set join_buffer_size= @save_join_buffer_size; set max_heap_table_size= @save_max_heap_table_size; explain select * from t1 where a in (select b from t2); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED t2 index b b 5 NULL 20 Using index select * from t1; a b 1 1 1 1 2 2 select * from t1 where a in (select b from t2); a b 1 1 1 1 2 2 drop table t1, t2, t3; set @save_join_buffer_size = @@join_buffer_size; set join_buffer_size= 8192; create table t1 (a int, filler1 binary(200), filler2 binary(200)); insert into t1 select a, 'filler123456', 'filler123456' from t0; insert into t1 select a+10, 'filler123456', 'filler123456' from t0; create table t2 as select * from t1; insert into t1 select a+20, 'filler123456', 'filler123456' from t0; insert into t1 values (2, 'duplicate ok', 'duplicate ok'); insert into t1 values (18, 'duplicate ok', 'duplicate ok'); insert into t2 values (3, 'duplicate ok', 'duplicate ok'); insert into t2 values (19, 'duplicate ok', 'duplicate ok'); explain select a, mid(filler1, 1,10), length(filler1)=length(filler2) as Z from t1 ot where a in (select a from t2 it); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY ALL distinct_key NULL NULL NULL 22 1 PRIMARY ot hash_ALL NULL #hash#$hj 5 test.it.a 32 Using where; Using join buffer (flat, BNLH join) 2 MATERIALIZED it ALL NULL NULL NULL NULL 22 Using where select a, mid(filler1, 1,10), length(filler1)=length(filler2) as Z from t1 ot where a in (select a from t2 it); a mid(filler1, 1,10) Z 0 filler1234 1 1 filler1234 1 2 filler1234 1 3 filler1234 1 4 filler1234 1 5 filler1234 1 6 filler1234 1 7 filler1234 1 8 filler1234 1 9 filler1234 1 10 filler1234 1 11 filler1234 1 12 filler1234 1 13 filler1234 1 14 filler1234 1 15 filler1234 1 16 filler1234 1 17 filler1234 1 18 filler1234 1 19 filler1234 1 2 duplicate 1 18 duplicate 1 explain select a, mid(filler1, 1,10), length(filler1)=length(filler2) from t2 ot where a in (select a from t1 it); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY ot ALL NULL NULL NULL NULL 22 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED it ALL NULL NULL NULL NULL 32 select a, mid(filler1, 1,10), length(filler1)=length(filler2) from t2 ot where a in (select a from t1 it); a mid(filler1, 1,10) length(filler1)=length(filler2) 0 filler1234 1 1 filler1234 1 2 filler1234 1 3 filler1234 1 4 filler1234 1 5 filler1234 1 6 filler1234 1 7 filler1234 1 8 filler1234 1 9 filler1234 1 10 filler1234 1 11 filler1234 1 12 filler1234 1 13 filler1234 1 14 filler1234 1 15 filler1234 1 16 filler1234 1 17 filler1234 1 18 filler1234 1 19 filler1234 1 3 duplicate 1 19 duplicate 1 insert into t1 select a+20, 'filler123456', 'filler123456' from t0; insert into t1 select a+20, 'filler123456', 'filler123456' from t0; explain select a, mid(filler1, 1,10), length(filler1)=length(filler2) as Z from t1 ot where a in (select a from t2 it); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY ALL distinct_key NULL NULL NULL 22 1 PRIMARY ot hash_ALL NULL #hash#$hj 5 test.it.a 52 Using where; Using join buffer (flat, BNLH join) 2 MATERIALIZED it ALL NULL NULL NULL NULL 22 Using where select a, mid(filler1, 1,10), length(filler1)=length(filler2) as Z from t1 ot where a in (select a from t2 it); a mid(filler1, 1,10) Z 0 filler1234 1 1 filler1234 1 2 filler1234 1 3 filler1234 1 4 filler1234 1 5 filler1234 1 6 filler1234 1 7 filler1234 1 8 filler1234 1 9 filler1234 1 10 filler1234 1 11 filler1234 1 12 filler1234 1 13 filler1234 1 14 filler1234 1 15 filler1234 1 16 filler1234 1 17 filler1234 1 18 filler1234 1 19 filler1234 1 2 duplicate 1 18 duplicate 1 explain select a, mid(filler1, 1,10), length(filler1)=length(filler2) from t2 ot where a in (select a from t1 it); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY ot ALL NULL NULL NULL NULL 22 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED it ALL NULL NULL NULL NULL 52 select a, mid(filler1, 1,10), length(filler1)=length(filler2) from t2 ot where a in (select a from t1 it); a mid(filler1, 1,10) length(filler1)=length(filler2) 0 filler1234 1 1 filler1234 1 2 filler1234 1 3 filler1234 1 4 filler1234 1 5 filler1234 1 6 filler1234 1 7 filler1234 1 8 filler1234 1 9 filler1234 1 10 filler1234 1 11 filler1234 1 12 filler1234 1 13 filler1234 1 14 filler1234 1 15 filler1234 1 16 filler1234 1 17 filler1234 1 18 filler1234 1 19 filler1234 1 3 duplicate 1 19 duplicate 1 drop table t1, t2; create table t1 (a int, b int, key(a)); create table t2 (a int, b int, key(a)); create table t3 (a int, b int, key(a)); insert into t1 select a,a from t0; insert into t2 select a,a from t0; insert into t3 select a,a from t0; t2 and t3 must be use 'ref', not 'ALL': explain select * from t0 where a in (select t2.a+t3.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 PRIMARY t0 ALL NULL NULL NULL NULL 10 1 PRIMARY eq_ref distinct_key distinct_key 8 func 1 Using where 2 MATERIALIZED t1 index a a 5 NULL 10 Using where; Using index 2 MATERIALIZED t2 ref a a 5 test.t1.a 1 Using index 2 MATERIALIZED t3 ref a a 5 test.t1.a 1 Using index drop table t0, t1,t2,t3; CREATE TABLE t1 ( ID int(11) NOT NULL auto_increment, Name char(35) NOT NULL default '', Country char(3) NOT NULL default '', Population int(11) NOT NULL default '0', PRIMARY KEY (ID), INDEX (Population), INDEX (Country) ); CREATE TABLE t2 ( Code char(3) NOT NULL default '', Name char(52) NOT NULL default '', SurfaceArea float(10,2) NOT NULL default '0.00', Population int(11) NOT NULL default '0', Capital int(11) default NULL, PRIMARY KEY (Code), UNIQUE INDEX (Name), INDEX (Population) ); CREATE TABLE t3 ( Country char(3) NOT NULL default '', Language char(30) NOT NULL default '', Percentage float(3,1) NOT NULL default '0.0', PRIMARY KEY (Country, Language), INDEX (Percentage) ); set @bug35674_save_optimizer_switch=@@optimizer_switch; set optimizer_switch='materialization=off'; EXPLAIN SELECT Name FROM t2 WHERE t2.Code IN (SELECT Country FROM t1 WHERE Population > 5000000) AND t2.Code IN (SELECT Country FROM t3 WHERE Language='English' AND Percentage > 10 AND t2.Population > 100000); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 range Population,Country Population 4 NULL 1 Using index condition; Rowid-ordered scan; Start temporary 1 PRIMARY t2 eq_ref PRIMARY,Population PRIMARY 3 test.t1.Country 1 Using where; End temporary; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan 1 PRIMARY t3 eq_ref PRIMARY,Percentage PRIMARY 33 test.t1.Country,const 1 Using index condition; Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan set optimizer_switch=@bug35674_save_optimizer_switch; DROP TABLE t1,t2,t3; CREATE TABLE t1 ( Code char(3) NOT NULL DEFAULT '', Name char(52) NOT NULL DEFAULT '', Continent enum('Asia','Europe','North America','Africa','Oceania','Antarctica','South America') NOT NULL DEFAULT 'Asia', Region char(26) NOT NULL DEFAULT '', SurfaceArea float(10,2) NOT NULL DEFAULT '0.00', IndepYear smallint(6) DEFAULT NULL, Population int(11) NOT NULL DEFAULT '0', LifeExpectancy float(3,1) DEFAULT NULL, GNP float(10,2) DEFAULT NULL, GNPOld float(10,2) DEFAULT NULL, LocalName char(45) NOT NULL DEFAULT '', GovernmentForm char(45) NOT NULL DEFAULT '', HeadOfState char(60) DEFAULT NULL, Capital int(11) DEFAULT NULL, Code2 char(2) NOT NULL DEFAULT '', PRIMARY KEY (Code) ); CREATE TABLE t2 ( ID int(11) NOT NULL AUTO_INCREMENT, Name char(35) NOT NULL DEFAULT '', CountryCode char(3) NOT NULL DEFAULT '', District char(20) NOT NULL DEFAULT '', Population int(11) NOT NULL DEFAULT '0', PRIMARY KEY (ID), KEY CountryCode (CountryCode) ); Fill the table with test data This must not use LooseScan: EXPLAIN SELECT Name FROM t1 WHERE t1.Code IN ( SELECT t2.CountryCode FROM t2 WHERE Population > 5000000); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL PRIMARY NULL NULL NULL 31 1 PRIMARY eq_ref distinct_key distinct_key 3 func 1 2 MATERIALIZED t2 ALL CountryCode NULL NULL NULL 545 Using where SELECT Name FROM t1 WHERE t1.Code IN ( SELECT t2.CountryCode FROM t2 WHERE Population > 5000000); Name Austria Canada China Czech Republic drop table t1, t2; drop procedure if exists p1; drop procedure if exists p2; drop procedure if exists p3; drop procedure if exists p4; CREATE TABLE t1(a INT); CREATE TABLE t2(c INT); CREATE PROCEDURE p1(v1 int) BEGIN SELECT 1 FROM t1 WHERE a = v1 AND a IN (SELECT c FROM t2); END // CREATE PROCEDURE p2(v1 int) BEGIN SELECT 1 FROM t1 WHERE a IN (SELECT c FROM t2); END // CREATE PROCEDURE p3(v1 int) BEGIN SELECT 1 FROM t1 t01,t1 t02,t1 t03,t1 t04,t1 t05,t1 t06,t1 t07,t1 t08, t1 t09,t1 t10,t1 t11,t1 t12,t1 t13,t1 t14,t1 t15,t1 t16, t1 t17,t1 t18,t1 t19,t1 t20,t1 t21,t1 t22,t1 t23,t1 t24, t1 t25,t1 t26,t1 t27,t1 t28,t1 t29,t1 t30,t1 t31,t1 t32, t1 t33,t1 t34,t1 t35,t1 t36,t1 t37,t1 t38,t1 t39,t1 t40, t1 t41,t1 t42,t1 t43,t1 t44,t1 t45,t1 t46,t1 t47,t1 t48, t1 t49,t1 t50,t1 t51,t1 t52,t1 t53,t1 t54,t1 t55,t1 t56, t1 t57,t1 t58,t1 t59,t1 t60 WHERE t01.a IN (SELECT c FROM t2); END // CREATE PROCEDURE p4(v1 int) BEGIN SELECT 1 FROM t1 t01,t1 t02,t1 t03,t1 t04,t1 t05,t1 t06,t1 t07,t1 t08, t1 t09,t1 t10,t1 t11,t1 t12,t1 t13,t1 t14,t1 t15,t1 t16, t1 t17,t1 t18,t1 t19,t1 t20,t1 t21,t1 t22,t1 t23,t1 t24, t1 t25,t1 t26,t1 t27,t1 t28,t1 t29,t1 t30,t1 t31,t1 t32, t1 t33,t1 t34,t1 t35,t1 t36,t1 t37,t1 t38,t1 t39,t1 t40, t1 t41,t1 t42,t1 t43,t1 t44,t1 t45,t1 t46,t1 t47,t1 t48, t1 t49,t1 t50,t1 t51,t1 t52,t1 t53,t1 t54,t1 t55,t1 t56, t1 t57,t1 t58,t1 t59,t1 t60 WHERE t01.a = v1 AND t01.a IN (SELECT c FROM t2); END // CALL p1(1); 1 CALL p2(1); 1 CALL p3(1); 1 CALL p4(1); 1 DROP TABLE t1, t2; DROP PROCEDURE p1; DROP PROCEDURE p2; DROP PROCEDURE p3; DROP PROCEDURE p4; create table t0 (a int); insert into t0 values (0),(1),(2),(3),(4); create table t1 (a int, b int, key(a)); insert into t1 select a,a from t0; insert into t1 select a+5,a from t0; create table t2 (a int, b int, primary key(a)); insert into t2 select * from t1; Table t2, unlike table t1, should be displayed as pulled out explain extended select * from t0 where t0.a in ( select t1.a from t1,t2 where t2.a=t0.a and t1.b=t2.b); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t0 ALL NULL NULL NULL NULL 5 100.00 Using where 1 PRIMARY t2 eq_ref PRIMARY PRIMARY 4 test.t0.a 1 100.00 Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan 1 PRIMARY t1 ref a a 5 test.t0.a 1 100.00 Using where; FirstMatch(t2); Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan Warnings: Note 1276 Field or reference 'test.t0.a' of SELECT #2 was resolved in SELECT #1 Note 1003 select `test`.`t0`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) join `test`.`t0` where ((`test`.`t2`.`a` = `test`.`t0`.`a`) and (`test`.`t1`.`a` = `test`.`t0`.`a`) and (`test`.`t1`.`b` = `test`.`t2`.`b`)) update t1 set a=3, b=11 where a=4; update t2 set b=11 where a=3; # Not anymore: # The following query gives wrong result due to Bug#49129 select * from t0 where t0.a in (select t1.a from t1, t2 where t2.a=t0.a and t1.b=t2.b); a 0 1 2 3 drop table t0, t1, t2; CREATE TABLE t1 ( id int(11) NOT NULL, PRIMARY KEY (id)); CREATE TABLE t2 ( id int(11) NOT NULL, fid int(11) NOT NULL, PRIMARY KEY (id)); insert into t1 values(1); insert into t2 values(1,7503),(2,1); explain select count(*) from t1 where fid IN (select fid from t2 where (id between 7502 and 8420) order by fid ); ERROR 42S22: Unknown column 'fid' in 'IN/ALL/ANY subquery' drop table t1, t2; create table t1 (a int, b int, key (a), key (b)); insert into t1 values (2,4),(2,4),(2,4); select t1.a from t1 where t1.a in (select 1 from t1 where t1.a in (select 1 from t1) group by t1.a); a drop table t1; create table t1(a int,b int,key(a),key(b)); insert into t1 values (1,1),(2,2),(3,3); select 1 from t1 where t1.a not in (select 1 from t1 where t1.a in (select 1 from t1) group by t1.b); 1 1 1 drop table t1; CREATE TABLE t1 (EMPNUM CHAR(3) NOT NULL, EMPNAME CHAR(20), GRADE DECIMAL(4), CITY CHAR(15)); CREATE TABLE t2 (PNUM CHAR(3) NOT NULL, PNAME CHAR(20), PTYPE CHAR(6), BUDGET DECIMAL(9), CITY CHAR(15)); CREATE TABLE t3 (EMPNUM CHAR(3) NOT NULL, PNUM CHAR(3) NOT NULL, HOURS DECIMAL(5)); INSERT INTO t1 VALUES ('E1','Alice',12,'Deale'); INSERT INTO t1 VALUES ('E2','Betty',10,'Vienna'); INSERT INTO t1 VALUES ('E3','Carmen',13,'Vienna'); INSERT INTO t1 VALUES ('E4','Don',12,'Deale'); INSERT INTO t1 VALUES ('E5','Ed',13,'Akron'); INSERT INTO t2 VALUES ('P1','MXSS','Design',10000,'Deale'); INSERT INTO t2 VALUES ('P2','CALM','Code',30000,'Vienna'); INSERT INTO t2 VALUES ('P3','SDP','Test',30000,'Tampa'); INSERT INTO t2 VALUES ('P4','SDP','Design',20000,'Deale'); INSERT INTO t2 VALUES ('P5','IRM','Test',10000,'Vienna'); INSERT INTO t2 VALUES ('P6','PAYR','Design',50000,'Deale'); INSERT INTO t3 VALUES ('E1','P1',40); INSERT INTO t3 VALUES ('E1','P2',20); INSERT INTO t3 VALUES ('E1','P3',80); INSERT INTO t3 VALUES ('E1','P4',20); INSERT INTO t3 VALUES ('E1','P5',12); INSERT INTO t3 VALUES ('E1','P6',12); INSERT INTO t3 VALUES ('E2','P1',40); INSERT INTO t3 VALUES ('E2','P2',80); INSERT INTO t3 VALUES ('E3','P2',20); INSERT INTO t3 VALUES ('E4','P2',20); INSERT INTO t3 VALUES ('E4','P4',40); INSERT INTO t3 VALUES ('E4','P5',80); SELECT * FROM t1; EMPNUM EMPNAME GRADE CITY E1 Alice 12 Deale E2 Betty 10 Vienna E3 Carmen 13 Vienna E4 Don 12 Deale E5 Ed 13 Akron CREATE UNIQUE INDEX t1_IDX ON t1(EMPNUM); SELECT EMPNAME FROM t1 WHERE EMPNUM IN (SELECT EMPNUM FROM t3 WHERE PNUM IN (SELECT PNUM FROM t2 WHERE PTYPE = 'Design')); EMPNAME Alice Betty Don DROP INDEX t1_IDX ON t1; CREATE INDEX t1_IDX ON t1(EMPNUM); SELECT EMPNAME FROM t1 WHERE EMPNUM IN (SELECT EMPNUM FROM t3 WHERE PNUM IN (SELECT PNUM FROM t2 WHERE PTYPE = 'Design')); EMPNAME Alice Betty Don DROP INDEX t1_IDX ON t1; SELECT EMPNAME FROM t1 WHERE EMPNUM IN (SELECT EMPNUM FROM t3 WHERE PNUM IN (SELECT PNUM FROM t2 WHERE PTYPE = 'Design')); EMPNAME Alice Betty Don DROP TABLE t1, t2, t3; CREATE TABLE t1 (f1 INT NOT NULL); CREATE VIEW v1 (a) AS SELECT f1 IN (SELECT f1 FROM t1) FROM t1; SELECT * FROM v1; a drop view v1; drop table t1; create table t0 (a int); insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); create table t1(a int, b int); insert into t1 values (0,0),(1,1),(2,2); create table t2 as select * from t1; create table t3 (pk int, a int, primary key(pk)); insert into t3 select a,a from t0; explain select * from t1 left join t2 on (t2.a= t1.a and t2.a in (select pk from t3)); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 1 PRIMARY t2 hash_ALL NULL #hash#$hj 5 test.t1.a 3 Using where; Using join buffer (flat, BNLH join) 2 MATERIALIZED t3 index PRIMARY PRIMARY 4 NULL 10 Using index drop table t0, t1, t2, t3; create table t1 (a int); insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); create table t2 (a char(200), b char(200), c char(200), primary key (a,b,c)) engine=innodb; insert into t2 select concat(a, repeat('X',198)),repeat('B',200),repeat('B',200) from t1; insert into t2 select concat(a, repeat('Y',198)),repeat('B',200),repeat('B',200) from t1; alter table t2 add filler1 int; insert into t1 select A.a + 10*(B.a + 10*C.a) from t1 A, t1 B, t1 C; set @save_join_buffer_size=@@join_buffer_size; set join_buffer_size=1; select * from t2 where filler1 in ( select a from t1); a b c filler1 set join_buffer_size=default; drop table t1, t2; create table t1 (a int not null); drop procedure if exists p1; CREATE PROCEDURE p1() BEGIN DECLARE EXIT HANDLER FOR SQLEXCEPTION select a from t1; prepare s1 from ' select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1 where a in ( select a from t1) )))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))'; execute s1; END; | call p1(); a drop procedure p1; drop table t1; create table t0 (a int); insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); create table t1 (a int) as select A.a + 10 *(B.a + 10*C.a) as a from t0 A, t0 B, t0 C; create table t2 (id int, a int, primary key(id), key(a)) as select a as id, a as a from t1; show create table t2; Table Create Table t2 CREATE TABLE `t2` ( `id` int(11) NOT NULL, `a` int(11) DEFAULT NULL, PRIMARY KEY (`id`), KEY `a` (`a`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 set @a=0; create table t3 as select * from t2 limit 0; insert into t3 select @a:=@a+1, t2.a from t2, t0; insert into t3 select @a:=@a+1, t2.a from t2, t0; insert into t3 select @a:=@a+1, t2.a from t2, t0; alter table t3 add primary key(id), add key(a); The following must use loose index scan over t3, key a: explain select count(a) from t2 where a in ( SELECT a FROM t3); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 index a a 5 NULL 1000 Using index 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED t3 index a a 5 NULL 30000 Using index select count(a) from t2 where a in ( SELECT a FROM t3); count(a) 1000 drop table t0,t1,t2,t3; BUG#42740: crash in optimize_semijoin_nests create table t1 (c6 timestamp,key (c6)) engine=innodb; create table t2 (c2 double) engine=innodb; explain select 1 from t2 where c2 = any (select log10(null) from t1 where c6 eq_ref distinct_key distinct_key 4 func 1 Using where 1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using join buffer (flat, BNL join) 1 PRIMARY t3 ALL NULL NULL NULL NULL 2 FirstMatch((sj-nest)); Using join buffer (incremental, BNL join) 3 MATERIALIZED t2 ALL NULL NULL NULL NULL 1 drop table t2, t3; # # BUG#761598: InnoDB: Error: row_search_for_mysql() is called without ha_innobase::external_lock() in maria-5.3 # CREATE TABLE t1 ( f1 int NOT NULL , f10 int) ; INSERT IGNORE INTO t1 VALUES (25,0),(29,0); CREATE TABLE t2 ( f10 int) ENGINE=InnoDB; CREATE TABLE t3 ( f11 int) ; INSERT IGNORE INTO t3 VALUES (0); SELECT alias1.f10 AS field2 FROM t2 AS alias1 JOIN ( t3 AS alias2 JOIN t1 AS alias3 ON alias3.f10 ) ON alias3.f1 WHERE alias2.f11 IN ( SELECT SQ4_alias1.f10 FROM t1 AS SQ4_alias1 LEFT JOIN t2 AS SQ4_alias3 ON SQ4_alias3.f10 ) GROUP BY field2; field2 drop table t1, t2, t3; # # BUG#849763: Wrong result with second execution of prepared statement with semijoin + view # CREATE TABLE t1 ( c varchar(1)) engine=innodb; INSERT INTO t1 VALUES ('r'); CREATE TABLE t2 ( a integer, b varchar(1), c varchar(1)) engine=innodb; INSERT INTO t2 VALUES (1,'r','r'); CREATE OR REPLACE VIEW v1 AS SELECT * FROM t1; PREPARE st1 FROM 'SELECT * FROM t2 WHERE a = SOME (SELECT a FROM v1 WHERE v1.c = t2.c)'; EXECUTE st1; a b c 1 r r EXECUTE st1; a b c 1 r r DROP VIEW v1; DROP TABLE t1, t2; # # BUG#858732: Wrong result with semijoin + loosescan + comma join # CREATE TABLE t1 (f13 int(11) NOT NULL , PRIMARY KEY (f13)) ENGINE=InnoDB; INSERT INTO t1 VALUES (16),(24); CREATE TABLE t2 (f14 int(11) NOT NULL, f12 varchar(1) NOT NULL, KEY (f12,f14)) ENGINE=InnoDB; INSERT INTO t2 VALUES (6,'y'); CREATE TABLE t3 (f12 varchar(1) NOT NULL) ENGINE=InnoDB; INSERT INTO t3 VALUES ('r'),('s'),('t'),('v'),('w'),('x'),('y'); # The following must use LooseScan but not join buffering explain SELECT * FROM t3 WHERE f12 IN (SELECT alias2.f12 FROM t1 AS alias1, t2 AS alias2, t1 WHERE alias1.f13 = 24); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY alias1 const PRIMARY PRIMARY 4 const 1 Using index 1 PRIMARY alias2 index f12 f12 7 NULL 1 Using index; LooseScan 1 PRIMARY t1 index NULL PRIMARY 4 NULL 2 Using index; FirstMatch(alias2) 1 PRIMARY t3 ALL NULL NULL NULL NULL 7 Using where; Using join buffer (flat, BNL join) SELECT * FROM t3 WHERE f12 IN (SELECT alias2.f12 FROM t1 AS alias1, t2 AS alias2, t1 WHERE alias1.f13 = 24); f12 y DROP TABLE t1,t2,t3; # # BUG#869012: Wrong result with semijoin + materialization + AND in WHERE # CREATE TABLE t1 (f3 varchar(1) , f4 varchar(1) ) engine=InnoDB; INSERT IGNORE INTO t1 VALUES ('x','x'),('x','x'); CREATE TABLE t2 ( f4 varchar(1) ) ; INSERT IGNORE INTO t2 VALUES ('g'); CREATE TABLE t3 (f4 varchar(1) ) Engine=InnoDB; INSERT IGNORE INTO t3 VALUES ('x'); set @tmp_869012=@@optimizer_switch; SET optimizer_switch='semijoin=on,materialization=on'; SELECT * FROM t1 , t2 WHERE ( t1.f4 ) IN ( SELECT f4 FROM t3 ) AND t2.f4 != t1.f3 ; f3 f4 f4 x x g x x g set optimizer_switch= @tmp_869012; DROP TABLE t1,t2,t3; # # BUG#869001: Wrong result with semijoin + materialization + firstmatch + multipart key # set @tmp869001_jcl= @@join_cache_level; set @tmp869001_os= @@optimizer_switch; SET join_cache_level=0; SET optimizer_switch='materialization=on,semijoin=on,firstmatch=on,loosescan=off'; CREATE TABLE t1 ( f2 int, f3 varchar(1), KEY (f3,f2)) engine=innodb; INSERT INTO t1 VALUES (8,'x'),(NULL,'x'),(8,'c'); CREATE TABLE t2 ( f4 varchar(1)) engine=innodb; INSERT INTO t2 VALUES ('x'); CREATE TABLE t3 ( f1 int) engine=innodb; INSERT INTO t3 VALUES (8),(6),(2),(9),(6); CREATE TABLE t4 ( f3 varchar(1)) engine=innodb; INSERT INTO t4 VALUES ('p'),('j'),('c'); SELECT * FROM t1 JOIN t2 ON (t2.f4 = t1.f3 ) WHERE ( 8 ) IN ( SELECT t3.f1 FROM t3 , t4 ); f2 f3 f4 NULL x x 8 x x DROP TABLE t1, t2, t3, t4; set join_cache_level= @tmp869001_jcl; set optimizer_switch= @tmp869001_os; # # Bug #881318: join cache + duplicate elimination + left join # with empty materialized derived inner table # CREATE TABLE t1 (b varchar(1)) ENGINE=InnoDB; CREATE TABLE t2 (a varchar(1)) ENGINE=InnoDB; INSERT INTO t2 VALUES ('a'); CREATE TABLE t3 (a varchar(1), b varchar(1)) ENGINE=InnoDB; INSERT INTO t3 VALUES ('c','c'); CREATE TABLE t4 (b varchar(1)) ENGINE=InnoDB; INSERT INTO t4 VALUES ('c'), ('b'); CREATE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT * FROM t1; EXPLAIN SELECT * FROM t3 LEFT JOIN (v1,t2) ON t3.a = t2.a WHERE t3.b IN (SELECT b FROM t4); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 1 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 1 PRIMARY t2 hash_ALL NULL #hash#$hj 4 test.t3.a 1 Using where; Using join buffer (flat, BNLH join) 1 PRIMARY ALL NULL NULL NULL NULL 2 Using join buffer (incremental, BNL join) 2 MATERIALIZED t4 ALL NULL NULL NULL NULL 2 3 DERIVED t1 ALL NULL NULL NULL NULL 1 SELECT * FROM t3 LEFT JOIN (v1,t2) ON t3.a = t2.a WHERE t3.b IN (SELECT b FROM t4); a b b a c c NULL NULL DROP VIEW v1; DROP TABLE t1,t2,t3,t4; # # BUG#912538: Wrong result (missing rows) with semijoin=on, firstmatch=on, ... # CREATE TABLE t1 ( a INT NOT NULL, UNIQUE KEY(a) ); INSERT INTO t1 VALUES (1),(2),(3),(4); CREATE TABLE t2 ( b INT, c INT ) ENGINE=InnoDB; INSERT INTO t2 VALUES (1,1); SELECT * FROM t1, t2 WHERE c IN (SELECT c FROM t1, t2 WHERE a = b); a b c 1 1 1 2 1 1 3 1 1 4 1 1 DROP TABLE t1,t2; # # BUG#962667: Assertion `0' failed in QUICK_INDEX_SORT_SELECT::need_sorted_output() # with index_merge+index_merge_sort_union+loosescan+semijoin # CREATE TABLE t1 ( a INT, b VARCHAR(1), c INT, KEY(a), KEY(b) ) ENGINE=InnoDB; INSERT INTO t1 VALUES (1,'v',9),(2,'v',8),(3,'c',7),(4,'m',6),(5,'x',5), (6,'i',4),(7,'e',3),(8,'p',2),(9,'s',1),(10,'j',9), (11,'z',8),(12,'c',7),(13,'a',6),(14,'q',5),(15,'y',4), (16,'n',3),(17,'r',2),(18,'v',1),(19,'p',0); CREATE TABLE t2 ( pk INT, d VARCHAR(1), e INT, PRIMARY KEY(pk), KEY(d,e) ) ENGINE=InnoDB; INSERT INTO t2 VALUES (1,'x',1),(2,'d',2),(3,'r',3),(4,'f',4),(5,'y',5), (6,'u',6),(7,'m',7),(8,'k',8),(9,'o',9),(10,'w',1), (11,'m',2),(12,'q',3),(13,'m',4),(14,'d',5), (15,'g',6),(16,'x',7),(17,'f',8); explain SELECT * FROM t1 WHERE b IN ( SELECT d FROM t2, t1 WHERE a = d AND ( pk < 2 OR d = 'z' ) ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL b NULL NULL NULL 19 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED t2 index PRIMARY,d d 9 NULL 17 Using where; Using index 2 MATERIALIZED t1 ref a a 5 test.t2.d 1 Using where; Using index SELECT * FROM t1 WHERE b IN ( SELECT d FROM t2, t1 WHERE a = d AND ( pk < 2 OR d = 'z' ) ); a b c DROP TABLE t1, t2; # # BUG#951937: Wrong result (missing rows) with semijoin+materialization, IN subquery, InnoDB, TEMPTABLE view # CREATE TABLE t1 ( a VARCHAR(1), b VARCHAR(1) NOT NULL, KEY(a) ) ENGINE=InnoDB; INSERT INTO t1 VALUES ('j','j'),('v','v'),('c','c'),('m','m'),('d','d'), ('y','y'),('t','t'),('d','d'),('s','s'),('r','r'), ('m','m'),('b','b'),('x','x'),('g','g'),('p','p'), ('q','q'),('w','w'),('d','d'),('e','e'); CREATE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT * FROM t1; # This query returned 6 rows instead of 19 SELECT * FROM v1 WHERE ( a, a ) IN ( SELECT alias2.b, alias2.a FROM t1 AS alias1, t1 AS alias2 WHERE alias2.b = alias1.a AND ( alias1.b >= alias1.a OR alias2.b = 'z' ) ); a b b b c c d d d d d d e e g g j j m m m m p p q q r r s s t t v v w w x x y y # Another testcase, without the VIEW: CREATE TABLE t2 (a VARCHAR(1), b VARCHAR(1) NOT NULL, KEY(a)) ENGINE=InnoDB; INSERT INTO t2 SELECT * FROM t1; INSERT INTO t2 SELECT * FROM t1; EXPLAIN SELECT * FROM t2 WHERE (a, a) IN (SELECT alias2.b, alias2.a FROM t1 AS alias1, t1 AS alias2 WHERE alias2.b = alias1.a AND (alias1.b >= alias1.a OR alias2.b = 'z')); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 ALL a NULL NULL NULL 38 1 PRIMARY eq_ref distinct_key distinct_key 8 func,func 1 2 MATERIALIZED alias1 ALL a NULL NULL NULL 19 Using where 2 MATERIALIZED alias2 ref a a 4 test.alias1.a 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan SELECT * FROM t2 WHERE (a, a) IN (SELECT alias2.b, alias2.a FROM t1 AS alias1, t1 AS alias2 WHERE alias2.b = alias1.a AND (alias1.b >= alias1.a OR alias2.b = 'z')); a b b b b b c c c c d d d d d d d d d d d d e e e e g g g g j j j j m m m m m m m m p p p p q q q q r r r r s s s s t t t t v v v v w w w w x x x x y y y y DROP VIEW v1; DROP TABLE t1, t2; # # BUG#965872: Server crashes in embedding_sjm on a simple 1-table select with AND and OR # (this is a regression caused by the fix for BUG#951937) CREATE TABLE t1 ( a INT, b INT, c INT, d INT ); INSERT INTO t1 VALUES (4,2,8,9),(4,2,7,8); SELECT * FROM t1 WHERE a = d AND ( b = 50 AND b = d OR a = c ); a b c d DROP TABLE t1; # # BUG#951283: Wrong result (missing rows) with semijoin+firstmatch, IN/ANY subquery # set @tmp_951283=@@optimizer_prune_level; SET optimizer_prune_level=0; CREATE TABLE t1 ( a INT ) ENGINE=InnoDB; INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16), (17),(18),(19),(20),(21),(22),(23); CREATE TABLE t2 ( b INT PRIMARY KEY, c VARCHAR(1), d VARCHAR(1), KEY(c) ) ENGINE=InnoDB; INSERT INTO t2 VALUES (1,'j','j'),(2,'v','v'),(3,'c','c'),(4,'m','m'), (5,'d','d'),(6,'d','d'),(7,'y','y'),(8,'t','t'), (9,'d','d'),(10,'s','s'),(11,'r','r'),(12,'m','m'), (13,'b','b'),(14,'x','x'),(15,'g','g'),(16,'p','p'), (17,'q','q'),(18,'w','w'),(19,'d','d'); EXPLAIN SELECT COUNT(*) FROM t1 AS alias1, t1 AS alias2, t2 AS alias3 WHERE alias3.d IN ( SELECT alias4.c FROM t2 AS alias4, t2 AS alias5 WHERE alias5.b = alias4.b AND ( alias5.b >= alias3.b OR alias5.c != alias3.c ) ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY alias3 ALL PRIMARY NULL NULL NULL 19 Using where 1 PRIMARY alias4 ref PRIMARY,c c 4 test.alias3.d 1 Using index 1 PRIMARY alias5 eq_ref PRIMARY PRIMARY 4 test.alias4.b 1 Using where; FirstMatch(alias3) 1 PRIMARY alias2 ALL NULL NULL NULL NULL 14 Using join buffer (flat, BNL join) 1 PRIMARY alias1 ALL NULL NULL NULL NULL 14 Using join buffer (incremental, BNL join) SELECT COUNT(*) FROM t1 AS alias1, t1 AS alias2, t2 AS alias3 WHERE alias3.d IN ( SELECT alias4.c FROM t2 AS alias4, t2 AS alias5 WHERE alias5.b = alias4.b AND ( alias5.b >= alias3.b OR alias5.c != alias3.c ) ); COUNT(*) 3724 EXPLAIN SELECT COUNT(*) FROM t1 AS alias1, t1 AS alias2, t2 AS alias3 WHERE alias3.d IN ( SELECT alias4.c FROM t2 AS alias4, t2 AS alias5 WHERE alias5.b = alias4.b AND ( alias5.b >= alias3.b OR alias3.c != alias5.c ) ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY alias3 ALL PRIMARY NULL NULL NULL 19 Using where 1 PRIMARY alias4 ref PRIMARY,c c 4 test.alias3.d 1 Using index 1 PRIMARY alias5 eq_ref PRIMARY PRIMARY 4 test.alias4.b 1 Using where; FirstMatch(alias3) 1 PRIMARY alias2 ALL NULL NULL NULL NULL 14 Using join buffer (flat, BNL join) 1 PRIMARY alias1 ALL NULL NULL NULL NULL 14 Using join buffer (incremental, BNL join) SELECT COUNT(*) FROM t1 AS alias1, t1 AS alias2, t2 AS alias3 WHERE alias3.d IN ( SELECT alias4.c FROM t2 AS alias4, t2 AS alias5 WHERE alias5.b = alias4.b AND ( alias5.b >= alias3.b OR alias3.c != alias5.c ) ); COUNT(*) 3724 set optimizer_prune_level=@tmp_951283; DROP TABLE t1,t2; # # Bug mdev-5135: crash on semijoin with nested outer joins # CREATE TABLE t1 (i1 int) ENGINE=MyISAM; INSERT INTO t1 VALUES (1),(2); CREATE TABLE t2 (i2 int, INDEX(i2)) ENGINE=MyISAM; CREATE TABLE t3 (i3 int, c varchar(1), INDEX(i3), INDEX(c)) ENGINE=MyISAM; INSERT INTO t3 VALUES (3,'x'),(4,'y'); SELECT * FROM t1 WHERE ( 1, 1 ) IN ( SELECT i2, i2 FROM t2 LEFT OUTER JOIN ( t3 AS t3a INNER JOIN t3 AS t3b ON ( t3a.i3 = t3b.i3 ) ) ON ( t3a.c = t3b.c ) ); i1 DROP TABLE t1,t2,t3; # # MDEV-5582: Plugin 'MEMORY' has ref_count=1 after shutdown with materialization+semijoin # CREATE TABLE t1 (a INT) engine=innodb; INSERT INTO t1 VALUES (8),(9); CREATE TABLE t2 (b INT) engine=innodb; INSERT INTO t2 VALUES (2),(3); CREATE TABLE t3 (c INT, INDEX(c)) engine=innodb; INSERT INTO t2 VALUES (4),(5); explain SELECT * FROM t1 WHERE 9 IN ( SELECT b FROM t2 WHERE 1 IN ( SELECT MIN(c) FROM t3 ) ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE 3 MATERIALIZED NULL NULL NULL NULL NULL NULL NULL No matching min/max row SELECT * FROM t1 WHERE 9 IN ( SELECT b FROM t2 WHERE 1 IN ( SELECT MIN(c) FROM t3 ) ); a DROP TABLE t1,t2,t3; DROP TABLE IF EXISTS t1,t2,t3,t4; # # MDEV-4782: Valgrind warnings (Conditional jump or move depends on uninitialised value) with InnoDB, semijoin # CREATE TABLE t1 ( t1_pk1 varchar(3), t1_pk2 varchar(52), PRIMARY KEY (t1_pk1,t1_pk2)) ENGINE=InnoDB; INSERT INTO t1 VALUES ('CHN','Chinese'),('USA','English'); CREATE TABLE t2 ( t2_i int(11), t2_c varchar(52)) ENGINE=InnoDB; INSERT INTO t2 VALUES (86,'English'); CREATE TABLE t3 ( t3_i int(11), t3_c varchar(35)) ENGINE=InnoDB; INSERT INTO t3 VALUES (3989,'Abilene'),(3873,'Akron'); create table t4 like t1; insert into t4 select * from t1; SELECT * FROM t1, t3 WHERE t3_c IN ( SELECT t1_pk2 FROM t4, t2 WHERE t2_c = t1_pk2 AND t2_i >= t3_i ) AND ( t1_pk1 = 'POL' ); t1_pk1 t1_pk2 t3_i t3_c explain SELECT * FROM t1, t3 WHERE t3_c IN ( SELECT t1_pk2 FROM t4, t2 WHERE t2_c = t1_pk2 AND t2_i >= t3_i ) AND ( t1_pk1 = 'POL' ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ref PRIMARY PRIMARY 5 const 1 Using where; Using index 1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Start temporary; Using join buffer (flat, BNL join) 1 PRIMARY t3 ALL NULL NULL NULL NULL 2 Using where; Using join buffer (incremental, BNL join) 1 PRIMARY t4 hash_index NULL #hash#$hj:PRIMARY 54:59 test.t3.t3_c 2 Using where; End temporary; Using join buffer (incremental, BNLH join) DROP TABLE t1,t2,t3,t4; # # MDEV-6263: Wrong result when using IN subquery with order by # CREATE TABLE t1 ( id int(11) NOT NULL, nombre varchar(255) NOT NULL, PRIMARY KEY (id) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO t1 (id, nombre) VALUES (1, 'row 1'),(2, 'row 2'),(3, 'row 3'), (4, 'row 4'),(5, 'row 5'),(6, 'row 6'); CREATE TABLE t2 ( id_algo int(11) NOT NULL, id_agente int(11) NOT NULL, PRIMARY KEY (id_algo,id_agente), KEY another_data (id_agente) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO t2 (id_algo, id_agente) VALUES (1, 1),(1, 2),(2, 1),(2, 2),(2, 3),(3, 1); SELECT * FROM t1 WHERE id in (select distinct id_agente from t2) ORDER BY nombre ASC; id nombre 1 row 1 2 row 2 3 row 3 SELECT * FROM t1 WHERE id in (select distinct id_agente from t2); id nombre 1 row 1 2 row 2 3 row 3 DROP TABLE t1, t2; # # MDEV-7474: Semi-Join's DuplicateWeedout strategy skipped for some values of optimizer_search_depth # CREATE TABLE t1 ( t1id BIGINT(20) NOT NULL, code VARCHAR(20), PRIMARY KEY (t1id) ) COLLATE='utf8mb4_bin' ENGINE=InnoDB; CREATE TABLE t2 ( t2id BIGINT(20) NOT NULL, t1idref BIGINT(20) NOT NULL, code VARCHAR(20), PRIMARY KEY (t2id), INDEX FK_T2_T1Id (t1idref), CONSTRAINT FK_T2_T1Id FOREIGN KEY (t1idref) REFERENCES t1 (t1id) ) COLLATE='utf8mb4_bin' ENGINE=InnoDB; CREATE TABLE t3 ( t3idref BIGINT(20) NOT NULL, t2idref BIGINT(20) NOT NULL, sequencenumber INT(10) NOT NULL, PRIMARY KEY (t3idref, t2idref), INDEX FK_T3_T2Id (t2idref), CONSTRAINT FK_T3_T2Id FOREIGN KEY (t2idref) REFERENCES t2 (t2id) ) COLLATE='utf8mb4_bin' ENGINE=InnoDB; INSERT INTO t1 (t1id) VALUES (100001),(100017),(100018),(100026),(100027),(100028),(100029),(100030), (100031),(100032),(100033),(100034),(100035),(100036),(100037),(100038),(100040),(100041),(100042), (100043),(100044),(100045),(100046),(100047); INSERT IGNORE INTO t2 (t2id, t1idref) SELECT t1id, t1id FROM t1; INSERT IGNORE INTO t1 VALUES (200001, 'a'); INSERT IGNORE INTO t2 (t2id, t1idref) VALUES (200011, 200001),(200012, 200001),(200013, 200001); INSERT IGNORE INTO t3 VALUES (1, 200011, 1), (1, 200012, 2), (1, 200013, 3); set @tmp7474= @@optimizer_search_depth; SET SESSION optimizer_search_depth = 1; SELECT SQL_NO_CACHE T2_0_.t1idref, T2_0_.t2id FROM t2 T2_0_ WHERE T2_0_.t1idref IN ( SELECT T1_1_.t1id FROM t3 T3_0_ INNER JOIN t2 T2_1_ ON T3_0_.t2idref=T2_1_.t2id INNER JOIN t1 T1_1_ ON T2_1_.t1idref=T1_1_.t1id WHERE T3_0_.t3idref= 1 ); t1idref t2id 200001 200011 200001 200012 200001 200013 explain SELECT SQL_NO_CACHE T2_0_.t1idref, T2_0_.t2id FROM t2 T2_0_ WHERE T2_0_.t1idref IN ( SELECT T1_1_.t1id FROM t3 T3_0_ INNER JOIN t2 T2_1_ ON T3_0_.t2idref=T2_1_.t2id INNER JOIN t1 T1_1_ ON T2_1_.t1idref=T1_1_.t1id WHERE T3_0_.t3idref= 1 ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY T3_0_ ref PRIMARY,FK_T3_T2Id PRIMARY 8 const 3 Using index; Start temporary 1 PRIMARY T2_1_ eq_ref PRIMARY,FK_T2_T1Id PRIMARY 8 test.T3_0_.t2idref 1 Using join buffer (flat, BKA join); Key-ordered scan 1 PRIMARY T1_1_ eq_ref PRIMARY PRIMARY 8 test.T2_1_.t1idref 1 Using index 1 PRIMARY T2_0_ ref FK_T2_T1Id FK_T2_T1Id 8 test.T2_1_.t1idref 1 Using index; End temporary drop table t3,t2,t1; set optimizer_search_depth=@tmp7474; # # # CREATE TABLE t1 ( id int(16) NOT NULL AUTO_INCREMENT, PRIMARY KEY (id) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE t2 ( id int(16) NOT NULL AUTO_INCREMENT, t3_id int(16) NOT NULL DEFAULT '0', t1_id int(16) NOT NULL DEFAULT '0', PRIMARY KEY (id), KEY t3_idx (t3_id), KEY t1_idx (t1_id) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; CREATE TABLE t3 ( id int(16) NOT NULL AUTO_INCREMENT, PRIMARY KEY (id) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; INSERT INTO t3 VALUES (1); INSERT INTO t2 VALUES (1, 1, 1); INSERT INTO t2 VALUES (2, 1, 2); INSERT INTO t2 VALUES (3, 1, 2); INSERT INTO t2 VALUES (4, 1, 1); INSERT INTO t1 VALUES (1); INSERT INTO t1 VALUES (2); SELECT * FROM t1 WHERE t1.id IN ( SELECT t2.t1_id FROM t3 JOIN t2 ON t3.id = t2.t3_id WHERE t3.id = 1 ); id 1 2 drop table t1,t2,t3; # This must be the last in the file: set optimizer_switch=@subselect_sj2_tmp; # # Bug #898073: potential incremental join cache for semijoin # CREATE TABLE t1 (a int, b varchar(1), KEY (b,a)); INSERT INTO t1 VALUES (0,'x'), (5,'r'); CREATE TABLE t2 (a int) ENGINE=InnoDB; INSERT INTO t2 VALUES (8); CREATE TABLE t3 (b varchar(1), c varchar(1)) ENGINE=InnoDB; INSERT INTO t3 VALUES ('x','x'); CREATE TABLE t4 (a int NOT NULL, b varchar(1)) ENGINE=InnoDB; INSERT INTO t4 VALUES (20,'r'), (10,'x'); set @tmp_optimizer_switch=@@optimizer_switch; SET SESSION optimizer_switch='semijoin_with_cache=on'; SET SESSION join_cache_level=2; EXPLAIN SELECT t3.* FROM t1 JOIN t3 ON t3.b = t1.b WHERE c IN (SELECT t4.b FROM t4 JOIN t2); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 1 Using where 1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using join buffer (flat, BNL join) 1 PRIMARY t4 ALL NULL NULL NULL NULL 2 Using where; FirstMatch(t3); Using join buffer (incremental, BNL join) 1 PRIMARY t1 ref b b 4 test.t3.b 1 Using index SELECT t3.* FROM t1 JOIN t3 ON t3.b = t1.b WHERE c IN (SELECT t4.b FROM t4 JOIN t2); b c x x set optimizer_switch=@tmp_optimizer_switch; set join_cache_level=default; DROP TABLE t1,t2,t3,t4; # # Bug #899696: potential incremental join cache for semijoin # CREATE TABLE t1 (pk int PRIMARY KEY, a int); INSERT INTO t1 VALUES (1, 6), (2, 8); CREATE TABLE t2 (b int) ENGINE=InnoDB; INSERT INTO t2 VALUES (8); CREATE TABLE t3 (pk int PRIMARY KEY, a int); INSERT INTO t3 VALUES (1, 6), (2, 8); CREATE TABLE t4 (b int) ENGINE=InnoDB; INSERT INTO t4 VALUES (2); set @tmp_optimizer_switch=@@optimizer_switch; SET optimizer_switch = 'semijoin_with_cache=on'; SET join_cache_level = 2; EXPLAIN SELECT * FROM t1, t2 WHERE b IN (SELECT a FROM t3, t4 WHERE b = pk); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 ALL NULL NULL NULL NULL 1 1 PRIMARY t4 ALL NULL NULL NULL NULL 1 Using where 1 PRIMARY t3 eq_ref PRIMARY PRIMARY 4 test.t4.b 1 Using where; FirstMatch(t2) 1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using join buffer (flat, BNL join) SELECT * FROM t1, t2 WHERE b IN (SELECT a FROM t3, t4 WHERE b = pk); pk a b 1 6 8 2 8 8 set optimizer_switch=@tmp_optimizer_switch; set join_cache_level=default; DROP TABLE t1,t2,t3,t4; # # Bug #899962: materialized subquery with join_cache_level=3 # CREATE TABLE t1 (a varchar(1), b varchar(1)) ENGINE=InnoDB; INSERT INTO t1 VALUES ('v','v'); CREATE TABLE t2 (a varchar(1), b varchar(1)) ENGINE=InnoDB; INSERT INTO t2 VALUES ('v','v'); set @tmp_optimizer_switch=@@optimizer_switch; SET optimizer_switch = 'semijoin_with_cache=on'; SET join_cache_level = 3; EXPLAIN SELECT * FROM t1 WHERE b IN (SELECT a FROM t2 GROUP BY a); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 1 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 2 MATERIALIZED t2 ALL NULL NULL NULL NULL 1 SELECT * FROM t1 WHERE b IN (SELECT a FROM t2 GROUP BY a); a b v v EXPLAIN SELECT * FROM t1 WHERE b IN (SELECT max(a) FROM t2 GROUP BY a); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 1 Using where 1 PRIMARY hash_ALL distinct_key #hash#distinct_key 4 test.t1.b 1 Using join buffer (flat, BNLH join) 2 MATERIALIZED t2 ALL NULL NULL NULL NULL 1 Using temporary SELECT * FROM t1 WHERE b IN (SELECT max(a) FROM t2 GROUP BY a); a b v v set optimizer_switch=@tmp_optimizer_switch; set join_cache_level=default; DROP TABLE t1,t2; set join_cache_level=default; show variables like 'join_cache_level'; Variable_name Value join_cache_level 2 set @@optimizer_switch=@save_optimizer_switch_jcl6; set @optimizer_switch_for_subselect_sj2_test=NULL; set @join_cache_level_subselect_sj2_test=NULL;