set optimizer_switch='materialization=on'; drop table if exists t0, t1, t2, t3; 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; 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 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 <subquery2> ALL distinct_key NULL NULL NULL 3 1 PRIMARY t2 ref b b 5 test.t1.a 2 2 SUBQUERY t1 ALL NULL NULL NULL NULL 3 Using where 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; 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 10 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 5 func 1 2 SUBQUERY 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 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= 8000; 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 <subquery2> ALL distinct_key NULL NULL NULL 10 1 PRIMARY t3 ref b b 5 test.t0.a 1 2 SUBQUERY t0 ALL NULL NULL NULL NULL 10 Using where set @save_ecp= @@engine_condition_pushdown; set engine_condition_pushdown=0; 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 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 10 10 10 10 11 11 11 11 12 12 12 12 13 13 13 13 set engine_condition_pushdown=@save_ecp; 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 <subquery2> eq_ref distinct_key distinct_key 5 func 1 2 SUBQUERY t2 index b b 5 NULL 10 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= 8000; 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 <subquery2> ALL distinct_key NULL NULL NULL 22 1 PRIMARY ot ALL NULL NULL NULL NULL 32 Using where; Using join buffer (flat, BNL join) 2 SUBQUERY it ALL NULL NULL NULL NULL 22 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 <subquery2> eq_ref distinct_key distinct_key 5 func 1 2 SUBQUERY 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 <subquery2> ALL distinct_key NULL NULL NULL 22 1 PRIMARY ot ALL NULL NULL NULL NULL 52 Using where; Using join buffer (flat, BNL join) 2 SUBQUERY it ALL NULL NULL NULL NULL 22 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 <subquery2> eq_ref distinct_key distinct_key 5 func 1 2 SUBQUERY 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 <subquery2> eq_ref distinct_key distinct_key 9 func 1 2 SUBQUERY t1 index NULL a 5 NULL 10 Using index 2 SUBQUERY t2 ref a a 5 test.t1.a 1 Using where; Using index 2 SUBQUERY 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 1 PRIMARY t3 eq_ref PRIMARY,Percentage PRIMARY 33 test.t1.Country,const 1 Using index condition; Using where; End temporary 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 <subquery2> eq_ref distinct_key distinct_key 3 func 1 2 SUBQUERY 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; 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 t1 ref a a 5 test.t0.a 1 100.00 Start temporary 1 PRIMARY t2 eq_ref PRIMARY PRIMARY 4 test.t0.a 1 100.00 Using where; End temporary 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`.`b` = `test`.`t1`.`b`) and (`test`.`t1`.`a` = `test`.`t0`.`a`) and (`test`.`t2`.`a` = `test`.`t0`.`a`)) update t1 set a=3, b=11 where a=4; update t2 set b=11 where a=3; 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 ALL NULL NULL NULL NULL 3 Using where 2 DEPENDENT SUBQUERY t3 unique_subquery PRIMARY PRIMARY 4 func 1 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 DEFAULT '0', `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 <subquery2> eq_ref distinct_key distinct_key 5 func 1 2 SUBQUERY 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 <null) ; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables drop table t1, t2; # # BUG#42742: crash in setup_sj_materialization, Copy_field::set # create table t3 ( c1 year) engine=innodb; insert into t3 values (2135),(2142); create table t2 (c1 tinytext,c2 text,c6 timestamp) engine=innodb; # The following must not crash, EXPLAIN should show one SJ strategy, not a mix: explain select 1 from t2 where c2 in (select 1 from t3, t2) and c1 in (select convert(c6,char(1)) from t2); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using where 1 PRIMARY t2 ALL NULL NULL NULL NULL 1 1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using where 1 PRIMARY t3 ALL NULL NULL NULL NULL 2 FirstMatch(t2) 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; set optimizer_switch=default; select @@optimizer_switch like '%materialization=on%'; @@optimizer_switch like '%materialization=on%' 0