drop table if exists t1, t2, t3, t1i, t2i, t3i; drop table if exists columns; drop table if exists t1_16, t2_16, t3_16; drop view if exists v1, v2, v1m, v2m; create table t1 (a1 char(8), a2 char(8)); create table t2 (b1 char(8), b2 char(8)); create table t3 (c1 char(8), c2 char(8)); insert into t1 values ('1 - 00', '2 - 00'); insert into t1 values ('1 - 01', '2 - 01'); insert into t1 values ('1 - 02', '2 - 02'); insert into t2 values ('1 - 01', '2 - 01'); insert into t2 values ('1 - 01', '2 - 01'); insert into t2 values ('1 - 02', '2 - 02'); insert into t2 values ('1 - 02', '2 - 02'); insert into t2 values ('1 - 03', '2 - 03'); insert into t3 values ('1 - 01', '2 - 01'); insert into t3 values ('1 - 02', '2 - 02'); insert into t3 values ('1 - 03', '2 - 03'); insert into t3 values ('1 - 04', '2 - 04'); create table t1i (a1 char(8), a2 char(8)); create table t2i (b1 char(8), b2 char(8)); create table t3i (c1 char(8), c2 char(8)); create index it1i1 on t1i (a1); create index it1i2 on t1i (a2); create index it1i3 on t1i (a1, a2); create index it2i1 on t2i (b1); create index it2i2 on t2i (b2); create index it2i3 on t2i (b1, b2); create index it3i1 on t3i (c1); create index it3i2 on t3i (c2); create index it3i3 on t3i (c1, c2); insert into t1i select * from t1; insert into t2i select * from t2; insert into t3i select * from t3; set @@optimizer_switch='materialization=on,in_to_exists=off,firstmatch=off'; /****************************************************************************** * Simple tests. ******************************************************************************/ # non-indexed nullable fields explain extended select * from t1 where a1 in (select b1 from t2 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 9 func 1 100.00 2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`b1` > '0')) select * from t1 where a1 in (select b1 from t2 where b1 > '0'); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 9 test.t1.a1 1 100.00 2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using temporary Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`) join `test`.`t1` where (`<subquery2>`.`b1` = `test`.`t1`.`a1`) select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 test.t1.a1,test.t1.a2 1 100.00 2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using temporary Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`,`test`.`t2`.`b2`) join `test`.`t1` where ((`<subquery2>`.`b2` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`)) select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 test.t1.a1,test.t1.a2 1 100.00 2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using temporary Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1`,min(`test`.`t2`.`b2`) from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`) join `test`.`t1` where ((`<subquery2>`.`min(b2)` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`)) select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1i where a1 in (select b1 from t2i where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t2i index it2i1,it2i3 it2i1 # NULL 5 40.00 Using where; Using index; LooseScan 1 PRIMARY t1i ref _it1_idx _it1_idx # _ref_ 1 100.00 Warnings: Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) where ((`test`.`t1i`.`a1` = `test`.`t2i`.`b1`) and (`test`.`t2i`.`b1` > '0')) select * from t1i where a1 in (select b1 from t2i where b1 > '0'); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY <subquery2> ALL distinct_key # NULL # 3 100.00 # 1 PRIMARY t1i ref it1i1,it1i3 # 9 # 1 100.00 # 2 SUBQUERY t2i range it2i1,it2i3 # 9 # 3 100.00 # Warnings: Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1i` where (`test`.`t1i`.`a1` = `<subquery2>`.`b1`) select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t2i index it2i1,it2i2,it2i3 it2i3 # NULL 5 40.00 Using where; Using index; LooseScan 1 PRIMARY t1i ref _it1_idx _it1_idx # _ref_ 1 100.00 Warnings: Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) where ((`test`.`t1i`.`a2` = `test`.`t2i`.`b2`) and (`test`.`t1i`.`a1` = `test`.`t2i`.`b1`) and (`test`.`t2i`.`b1` > '0')) select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0'); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1i index it1i1,it1i2,it1i3 # # # 3 100.00 # 1 PRIMARY <subquery2> eq_ref distinct_key # # # 1 100.00 # 2 SUBQUERY t2i range it2i1,it2i3 # # # 3 100.00 # Warnings: Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,`test`.`t2i`.`b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`,`test`.`t2i`.`b2`) join `test`.`t1i` where ((`<subquery2>`.`b2` = `test`.`t1i`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1i`.`a1`)) select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1i index it1i1,it1i2,it1i3 # # # 3 100.00 # 1 PRIMARY <subquery2> eq_ref distinct_key # # # 1 100.00 # 2 SUBQUERY t2i range it2i1,it2i3 # # # 3 100.00 # Warnings: Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,min(`test`.`t2i`.`b2`) from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1i` where ((`<subquery2>`.`min(b2)` = `test`.`t1i`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1i`.`a1`)) select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 test.t1.a1,test.t1.a2 1 100.00 2 SUBQUERY t2i range NULL it2i3 9 NULL 3 100.00 Using index for group-by Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,max(`test`.`t2i`.`b2`) from `test`.`t2i` group by `test`.`t2i`.`b1`) join `test`.`t1` where ((`<subquery2>`.`max(b2)` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`)) select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 prepare st1 from "explain select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)"; execute st1; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 test.t1.a1,test.t1.a2 1 2 SUBQUERY t2i range NULL it2i3 9 NULL 3 Using index for group-by execute st1; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 test.t1.a1,test.t1.a2 1 2 SUBQUERY t2i range NULL it2i3 9 NULL 3 Using index for group-by prepare st2 from "select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)"; execute st2; a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 execute st2; a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 test.t1.a1,test.t1.a2 1 100.00 2 SUBQUERY t2i range it2i1,it2i3 it2i3 18 NULL 3 100.00 Using where; Using index for group-by Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,min(`test`.`t2i`.`b2`) from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1` where ((`<subquery2>`.`min(b2)` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`)) select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i limit 1,1); ERROR 42000: This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery' set @save_optimizer_switch=@@optimizer_switch; set @@optimizer_switch='default,semijoin=off'; prepare st1 from "select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)"; set @@optimizer_switch='default,materialization=off'; execute st1; a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 set @@optimizer_switch='default,semijoin=off'; execute st1; a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 set @@optimizer_switch='default,materialization=off'; prepare st1 from "select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)"; set @@optimizer_switch='default,semijoin=off'; execute st1; a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 set @@optimizer_switch='default,materialization=off'; execute st1; a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 set @@optimizer_switch=@save_optimizer_switch; explain extended select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 test.t1.a1,test.t1.a2 1 100.00 2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` order by `test`.`t2`.`b1`,`test`.`t2`.`b2`) join `test`.`t1` where ((`<subquery2>`.`b2` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`)) select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1i index it1i1,it1i2,it1i3 it1i3 18 NULL 3 100.00 Using where; Using index 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 test.t1i.a1,test.t1i.a2 1 100.00 2 SUBQUERY t2i index NULL it2i3 18 NULL 5 100.00 Using index Warnings: Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,`test`.`t2i`.`b2` from `test`.`t2i` order by `test`.`t2i`.`b1`,`test`.`t2i`.`b2`) join `test`.`t1i` where ((`<subquery2>`.`b2` = `test`.`t1i`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1i`.`a1`)) select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 /****************************************************************************** * Views, UNIONs, several levels of nesting. ******************************************************************************/ # materialize the result of subquery over temp-table view create algorithm=merge view v1 as select b1, c2 from t2, t3 where b2 > c2; create algorithm=merge view v2 as select b1, c2 from t2, t3 group by b2, c2; Warnings: Warning 1354 View merge algorithm can't be used here for now (assumed undefined algorithm) create algorithm=temptable view v1m as select b1, c2 from t2, t3 where b2 > c2; create algorithm=temptable view v2m as select b1, c2 from t2, t3 group by b2, c2; select * from v1 where (c2, b1) in (select c2, b1 from v2 where b1 is not null); b1 c2 1 - 02 2 - 01 1 - 02 2 - 01 1 - 03 2 - 01 1 - 03 2 - 02 select * from v1 where (c2, b1) in (select distinct c2, b1 from v2 where b1 is not null); b1 c2 1 - 02 2 - 01 1 - 02 2 - 01 1 - 03 2 - 01 1 - 03 2 - 02 select * from v1m where (c2, b1) in (select c2, b1 from v2m where b1 is not null); b1 c2 1 - 02 2 - 01 1 - 02 2 - 01 1 - 03 2 - 01 1 - 03 2 - 02 select * from v1m where (c2, b1) in (select distinct c2, b1 from v2m where b1 is not null); b1 c2 1 - 02 2 - 01 1 - 02 2 - 01 1 - 03 2 - 01 1 - 03 2 - 02 drop view v1, v2, v1m, v2m; explain extended select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0') and (a1, a2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 func,func 1 100.00 1 PRIMARY <subquery3> eq_ref distinct_key distinct_key 18 func,func 1 100.00 2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where 3 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where 3 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join) Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) semi join (`test`.`t2i` join `test`.`t3`) where ((`test`.`t2i`.`b2` = `test`.`t3`.`c2`) and (`test`.`t2i`.`b1` = `test`.`t3`.`c1`) and (`test`.`t2`.`b1` > '0') and (`test`.`t3`.`c2` > '0')) select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0') and (a1, a2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and (a1, a2) in (select c1, c2 from t3i where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1i index it1i1,it1i2,it1i3 # # # 3 100.00 # 1 PRIMARY <subquery2> eq_ref distinct_key # # # 1 100.00 # 1 PRIMARY <subquery3> eq_ref distinct_key # # # 1 100.00 # 2 SUBQUERY t2i index it2i1,it2i2,it2i3 # # # 5 100.00 # 3 SUBQUERY t2i index it2i1,it2i2,it2i3 # # # 5 100.00 # 3 SUBQUERY t3i index it3i1,it3i2,it3i3 # # # 4 75.00 # Warnings: Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) semi join (`test`.`t2i` join `test`.`t3i`) where ((`test`.`t3i`.`c2` = `test`.`t2i`.`b2`) and (`test`.`t3i`.`c1` = `test`.`t2i`.`b1`) and (`test`.`t2i`.`b1` > '0') and (`test`.`t2i`.`b2` > '0')) select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and (a1, a2) in (select c1, c2 from t3i where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1 where (a1, a2) in (select b1, b2 from t2 where b2 in (select c2 from t3 where c2 LIKE '%02') or b2 in (select c2 from t3 where c2 LIKE '%03')) and (a1, a2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 18 func,func 1 100.00 1 PRIMARY <subquery5> eq_ref distinct_key distinct_key 18 func,func 1 100.00 2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where 5 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where 5 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join) 4 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where 3 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) semi join (`test`.`t2i` join `test`.`t3`) where ((`test`.`t2i`.`b2` = `test`.`t3`.`c2`) and (`test`.`t2i`.`b1` = `test`.`t3`.`c1`) and (<expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery3>`.`c2`)))))) or <expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery4>`.`c2`))))))) and (`test`.`t3`.`c2` > '0')) select * from t1 where (a1, a2) in (select b1, b2 from t2 where b2 in (select c2 from t3 where c2 LIKE '%02') or b2 in (select c2 from t3 where c2 LIKE '%03')) and (a1, a2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); a1 a2 1 - 02 2 - 02 explain extended select * from t1 where (a1, a2) in (select b1, b2 from t2 where b2 in (select c2 from t3 t3a where c1 = a1) or b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and (a1, a2) in (select c1, c2 from t3 t3c where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Start temporary 1 PRIMARY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; End temporary; Using join buffer (flat, BNL join) 1 PRIMARY <subquery5> eq_ref distinct_key distinct_key 18 func,func 1 100.00 5 SUBQUERY t3c ALL NULL NULL NULL NULL 4 100.00 Using where 5 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join) 4 SUBQUERY t3b ALL NULL NULL NULL NULL 4 100.00 Using where 3 DEPENDENT SUBQUERY t3a ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Note 1276 Field or reference 'test.t1.a1' of SELECT #3 was resolved in SELECT #1 Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) semi join (`test`.`t2i` join `test`.`t3` `t3c`) where ((`test`.`t2`.`b2` = `test`.`t1`.`a2`) and (`test`.`t2i`.`b2` = `test`.`t3c`.`c2`) and (`test`.`t2`.`b1` = `test`.`t1`.`a1`) and (`test`.`t2i`.`b1` = `test`.`t3c`.`c1`) and (<expr_cache><`test`.`t2`.`b2`,`test`.`t1`.`a1`>(<in_optimizer>(`test`.`t2`.`b2`,<exists>(select `test`.`t3a`.`c2` from `test`.`t3` `t3a` where ((`test`.`t1`.`a1` = `test`.`t3a`.`c1`) and (<cache>(`test`.`t2`.`b2`) = `test`.`t3a`.`c2`))))) or <expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3b`.`c2` from `test`.`t3` `t3b` where (`test`.`t3b`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery4>`.`c2`))))))) and (`test`.`t3c`.`c2` > '0')) select * from t1 where (a1, a2) in (select b1, b2 from t2 where b2 in (select c2 from t3 t3a where c1 = a1) or b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and (a1, a2) in (select c1, c2 from t3 t3c where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended (select * from t1 where (a1, a2) in (select b1, b2 from t2 where b2 in (select c2 from t3 where c2 LIKE '%02') or b2 in (select c2 from t3 where c2 LIKE '%03') group by b1, b2) and (a1, a2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0'))) UNION (select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and (a1, a2) in (select c1, c2 from t3i where (c1, c2) in (select b1, b2 from t2i where b2 > '0'))); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY <subquery2> ALL distinct_key # # # 5 0.00 # 1 PRIMARY t3 ALL NULL # # # 4 100.00 # 1 PRIMARY t1 ALL NULL # # # 3 100.00 # 1 PRIMARY t2i ref it2i1,it2i2,it2i3 # # # 2 100.00 # 2 SUBQUERY t2 ALL NULL # # # 5 100.00 # 4 SUBQUERY t3 ALL NULL # # # 4 100.00 # 3 SUBQUERY t3 ALL NULL # # # 4 100.00 # 7 UNION t1i index it1i1,it1i2,it1i3 # # # 3 100.00 # 7 UNION <subquery8> eq_ref distinct_key # # # 1 100.00 # 7 UNION <subquery9> eq_ref distinct_key # # # 1 100.00 # 8 SUBQUERY t2i index it2i1,it2i2,it2i3 # # # 5 100.00 # 9 SUBQUERY t2i index it2i1,it2i2,it2i3 # # # 5 100.00 # 9 SUBQUERY t3i index it3i1,it3i2,it3i3 # # # 4 75.00 # NULL UNION RESULT <union1,7> ALL NULL # # # NULL NULL # Warnings: Note 1003 (select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` where (<expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery3>`.`c2`)))))) or <expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery4>`.`c2`))))))) group by `test`.`t2`.`b1`,`test`.`t2`.`b2`) semi join (`test`.`t2i` join `test`.`t3`) join `test`.`t1` where ((`test`.`t3`.`c2` = `<subquery2>`.`b2`) and (`test`.`t1`.`a2` = `<subquery2>`.`b2`) and (`test`.`t2i`.`b2` = `<subquery2>`.`b2`) and (`test`.`t3`.`c1` = `<subquery2>`.`b1`) and (`test`.`t1`.`a1` = `<subquery2>`.`b1`) and (`test`.`t2i`.`b1` = `<subquery2>`.`b1`) and (`<subquery2>`.`b2` > '0'))) union (select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) semi join (`test`.`t2i` join `test`.`t3i`) where ((`test`.`t3i`.`c2` = `test`.`t2i`.`b2`) and (`test`.`t3i`.`c1` = `test`.`t2i`.`b1`) and (`test`.`t2i`.`b1` > '0') and (`test`.`t2i`.`b2` > '0'))) (select * from t1 where (a1, a2) in (select b1, b2 from t2 where b2 in (select c2 from t3 where c2 LIKE '%02') or b2 in (select c2 from t3 where c2 LIKE '%03') group by b1, b2) and (a1, a2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0'))) UNION (select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and (a1, a2) in (select c1, c2 from t3i where (c1, c2) in (select b1, b2 from t2i where b2 > '0'))); a1 a2 1 - 02 2 - 02 1 - 01 2 - 01 explain extended select * from t1 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and (a1, a2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery4> eq_ref distinct_key distinct_key 18 func,func 1 100.00 4 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where 4 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join) 2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL 5 100.00 Using where NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2i` join `test`.`t3`) where ((`test`.`t2i`.`b2` = `test`.`t3`.`c2`) and (`test`.`t2i`.`b1` = `test`.`t3`.`c1`) and <expr_cache><`test`.`t1`.`a2`,`test`.`t1`.`a1`>(<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1`,`test`.`t1`.`a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`))))) and (`test`.`t3`.`c2` > '0')) select * from t1 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and (a1, a2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')); a1 a2 1 - 01 2 - 01 1 - 02 2 - 02 explain extended select * from t1, t3 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and (c1, c2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and a1 = c1; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY t3 ALL NULL NULL NULL NULL 4 100.00 Using where; Using join buffer (flat, BNL join) 1 PRIMARY <subquery4> eq_ref distinct_key distinct_key 18 func,func 1 100.00 4 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where 4 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join) 2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL 5 100.00 Using where NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,`test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t1` semi join (`test`.`t2i` join `test`.`t3`) join `test`.`t3` where ((`test`.`t2i`.`b2` = `test`.`t3`.`c2`) and (`test`.`t3`.`c1` = `test`.`t1`.`a1`) and (`test`.`t2i`.`b1` = `test`.`t3`.`c1`) and <expr_cache><`test`.`t1`.`a2`,`test`.`t1`.`a1`>(<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1`,`test`.`t1`.`a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`))))) and (`test`.`t3`.`c2` > '0')) select * from t1, t3 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and (c1, c2) in (select c1, c2 from t3 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and a1 = c1; a1 a2 c1 c2 1 - 01 2 - 01 1 - 01 2 - 01 1 - 02 2 - 02 1 - 02 2 - 02 /****************************************************************************** * Negative tests, where materialization should not be applied. ******************************************************************************/ # UNION in a subquery explain extended select * from t3 where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 4 100.00 Using where 2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL 5 100.00 Using where NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <expr_cache><`test`.`t3`.`c1`>(<in_optimizer>(`test`.`t3`.`c1`,<exists>(select `test`.`t1`.`a1` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t3`.`c1`) = `test`.`t1`.`a1`)) union select `test`.`t2`.`b1` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t3`.`c1`) = `test`.`t2`.`b1`))))) select * from t3 where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9'); c1 c2 1 - 01 2 - 01 1 - 02 2 - 02 1 - 03 2 - 03 explain extended select * from t1 where (a1, a2) in (select b1, b2 from t2 where b2 in (select c2 from t3 t3a where c1 = a1) or b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and (a1, a2) in (select c1, c2 from t3 t3c where (c1, c2) in (select b1, b2 from t2i where b2 > '0' or b2 = a2)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2i ref it2i1,it2i2,it2i3 it2i3 18 test.t1.a1,test.t1.a2 2 100.00 Using index 1 PRIMARY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using join buffer (flat, BNL join) 1 PRIMARY t3c ALL NULL NULL NULL NULL 4 100.00 Using where; End temporary; Using join buffer (flat, BNL join) 4 SUBQUERY t3b ALL NULL NULL NULL NULL 4 100.00 Using where 3 DEPENDENT SUBQUERY t3a ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Note 1276 Field or reference 'test.t1.a1' of SELECT #3 was resolved in SELECT #1 Note 1276 Field or reference 'test.t1.a2' of SELECT #6 was resolved in SELECT #1 Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) semi join (`test`.`t2i` join `test`.`t3` `t3c`) where ((`test`.`t2i`.`b2` = `test`.`t1`.`a2`) and (`test`.`t2`.`b2` = `test`.`t1`.`a2`) and (`test`.`t3c`.`c2` = `test`.`t1`.`a2`) and (`test`.`t2i`.`b1` = `test`.`t1`.`a1`) and (`test`.`t2`.`b1` = `test`.`t1`.`a1`) and (`test`.`t3c`.`c1` = `test`.`t1`.`a1`) and (<expr_cache><`test`.`t2`.`b2`,`test`.`t1`.`a1`>(<in_optimizer>(`test`.`t2`.`b2`,<exists>(select `test`.`t3a`.`c2` from `test`.`t3` `t3a` where ((`test`.`t1`.`a1` = `test`.`t3a`.`c1`) and (<cache>(`test`.`t2`.`b2`) = `test`.`t3a`.`c2`))))) or <expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3b`.`c2` from `test`.`t3` `t3b` where (`test`.`t3b`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery4>`.`c2`)))))))) explain extended select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL No tables used Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <expr_cache><`test`.`t1`.`a2`,`test`.`t1`.`a1`>(<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select '1 - 01','2 - 01' having (((<cache>(`test`.`t1`.`a1`) = '1 - 01') or isnull('1 - 01')) and ((<cache>(`test`.`t1`.`a2`) = '2 - 01') or isnull('2 - 01')) and <is_not_null_test>('1 - 01') and <is_not_null_test>('2 - 01'))))) select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01'); a1 a2 1 - 01 2 - 01 explain extended select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01' from dual); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where 2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL No tables used Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <expr_cache><`test`.`t1`.`a2`,`test`.`t1`.`a1`>(<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select '1 - 01','2 - 01' having (((<cache>(`test`.`t1`.`a1`) = '1 - 01') or isnull('1 - 01')) and ((<cache>(`test`.`t1`.`a2`) = '2 - 01') or isnull('2 - 01')) and <is_not_null_test>('1 - 01') and <is_not_null_test>('2 - 01'))))) select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01' from dual); a1 a2 1 - 01 2 - 01 /****************************************************************************** * Subqueries in other uncovered clauses. ******************************************************************************/ /* SELECT clause */ select ((a1,a2) IN (select * from t2 where b2 > '0')) IS NULL from t1; ((a1,a2) IN (select * from t2 where b2 > '0')) IS NULL 0 0 0 /* GROUP BY clause */ create table columns (col int key); insert into columns values (1), (2); explain extended select * from t1 group by (select col from columns limit 1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 2 SUBQUERY columns index NULL PRIMARY 4 NULL 2 100.00 Using index Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` group by (select `test`.`columns`.`col` from `test`.`columns` limit 1) select * from t1 group by (select col from columns limit 1); a1 a2 1 - 00 2 - 00 explain extended select * from t1 group by (a1 in (select col from columns)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using temporary; Using filesort 2 DEPENDENT SUBQUERY columns unique_subquery PRIMARY PRIMARY 4 func 1 100.00 Using index; Using where; Full scan on NULL key Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` group by <expr_cache><`test`.`t1`.`a1`>(<in_optimizer>(`test`.`t1`.`a1`,<exists>(<primary_index_lookup>(<cache>(`test`.`t1`.`a1`) in columns on PRIMARY where trigcond((<cache>(`test`.`t1`.`a1`) = `test`.`columns`.`col`)))))) select * from t1 group by (a1 in (select col from columns)); a1 a2 1 - 00 2 - 00 /* ORDER BY clause */ explain extended select * from t1 order by (select col from columns limit 1); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 2 SUBQUERY columns index NULL PRIMARY 4 NULL 2 100.00 Using index Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` order by (select `test`.`columns`.`col` from `test`.`columns` limit 1) select * from t1 order by (select col from columns limit 1); a1 a2 1 - 00 2 - 00 1 - 01 2 - 01 1 - 02 2 - 02 /****************************************************************************** * Column types/sizes that affect materialization. ******************************************************************************/ /* Test that BLOBs are not materialized (except when arguments of some functions). */ # force materialization to be always considered set @prefix_len = 6; set @blob_len = 16; set @suffix_len = @blob_len - @prefix_len; create table t1_16 (a1 blob(16), a2 blob(16)); create table t2_16 (b1 blob(16), b2 blob(16)); create table t3_16 (c1 blob(16), c2 blob(16)); insert into t1_16 values (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len))); insert into t1_16 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t1_16 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_16 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t2_16 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_16 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); insert into t3_16 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t3_16 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t3_16 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); insert into t3_16 values (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len))); explain extended select left(a1,7), left(a2,7) from t1_16 where a1 in (select b1 from t2_16 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` semi join (`test`.`t2_16`) where ((`test`.`t2_16`.`b1` = `test`.`t1_16`.`a1`) and (`test`.`t1_16`.`a1` > '0')) select left(a1,7), left(a2,7) from t1_16 where a1 in (select b1 from t2_16 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_16 where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` semi join (`test`.`t2_16`) where ((`test`.`t2_16`.`b2` = `test`.`t1_16`.`a2`) and (`test`.`t2_16`.`b1` = `test`.`t1_16`.`a1`) and (`test`.`t1_16`.`a1` > '0')) select left(a1,7), left(a2,7) from t1_16 where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_16 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 20 func 1 100.00 2 SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where Warnings: Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` semi join (`test`.`t2_16`) where ((`test`.`t2_16`.`b1` > '0') and (`test`.`t1_16`.`a1` = substr(`test`.`t2_16`.`b1`,1,16))) select left(a1,7), left(a2,7) from t1_16 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_16 where a1 in (select group_concat(b1) from t2_16 group by b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where 2 DEPENDENT SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using filesort Warnings: Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <expr_cache><`test`.`t1_16`.`a1`>(<in_optimizer>(`test`.`t1_16`.`a1`,<exists>(select group_concat(`test`.`t2_16`.`b1` separator ',') from `test`.`t2_16` group by `test`.`t2_16`.`b2` having (<cache>(`test`.`t1_16`.`a1`) = <ref_null_helper>(group_concat(`test`.`t2_16`.`b1` separator ',')))))) select left(a1,7), left(a2,7) from t1_16 where a1 in (select group_concat(b1) from t2_16 group by b2); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x set @@group_concat_max_len = 256; explain extended select left(a1,7), left(a2,7) from t1_16 where a1 in (select group_concat(b1) from t2_16 group by b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_16.a1 1 100.00 Using where 2 SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using filesort Warnings: Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_16`.`b1` separator ',') from `test`.`t2_16` group by `test`.`t2_16`.`b2`) join `test`.`t1_16` where (`test`.`t1_16`.`a1` = `<subquery2>`.`group_concat(b1)`) select left(a1,7), left(a2,7) from t1_16 where a1 in (select group_concat(b1) from t2_16 group by b2); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select * from t1 where concat(a1,'x') IN (select left(a1,8) from t1_16 where (a1, a2) IN (select t2_16.b1, t2_16.b2 from t2_16, t2 where t2.b2 = substring(t2_16.b2,1,6) and t2.b1 IN (select c1 from t3 where c2 > '0'))); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Start temporary 1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join) 1 PRIMARY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join) 1 PRIMARY t3 ALL NULL NULL NULL NULL 4 100.00 Using where; Using join buffer (flat, BNL join) 1 PRIMARY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t3` join `test`.`t2_16` join `test`.`t2` join `test`.`t1_16`) where ((`test`.`t2_16`.`b2` = `test`.`t1_16`.`a2`) and (`test`.`t2_16`.`b1` = `test`.`t1_16`.`a1`) and (`test`.`t2`.`b1` = `test`.`t3`.`c1`) and (`test`.`t2`.`b2` = substr(`test`.`t1_16`.`a2`,1,6)) and (`test`.`t3`.`c2` > '0') and (concat(`test`.`t1`.`a1`,'x') = left(`test`.`t1_16`.`a1`,8))) drop table t1_16, t2_16, t3_16; set @blob_len = 512; set @suffix_len = @blob_len - @prefix_len; create table t1_512 (a1 blob(512), a2 blob(512)); create table t2_512 (b1 blob(512), b2 blob(512)); create table t3_512 (c1 blob(512), c2 blob(512)); insert into t1_512 values (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len))); insert into t1_512 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t1_512 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_512 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t2_512 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_512 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); insert into t3_512 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t3_512 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t3_512 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); insert into t3_512 values (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len))); explain extended select left(a1,7), left(a2,7) from t1_512 where a1 in (select b1 from t2_512 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` semi join (`test`.`t2_512`) where ((`test`.`t2_512`.`b1` = `test`.`t1_512`.`a1`) and (`test`.`t1_512`.`a1` > '0')) select left(a1,7), left(a2,7) from t1_512 where a1 in (select b1 from t2_512 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_512 where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` semi join (`test`.`t2_512`) where ((`test`.`t2_512`.`b2` = `test`.`t1_512`.`a2`) and (`test`.`t2_512`.`b1` = `test`.`t1_512`.`a1`) and (`test`.`t1_512`.`a1` > '0')) select left(a1,7), left(a2,7) from t1_512 where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_512 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 517 func 1 100.00 2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where Warnings: Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` semi join (`test`.`t2_512`) where ((`test`.`t2_512`.`b1` > '0') and (`test`.`t1_512`.`a1` = substr(`test`.`t2_512`.`b1`,1,512))) select left(a1,7), left(a2,7) from t1_512 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_512 where a1 in (select group_concat(b1) from t2_512 group by b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_512.a1 1 100.00 Using where 2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using filesort Warnings: Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') from `test`.`t2_512` group by `test`.`t2_512`.`b2`) join `test`.`t1_512` where (`test`.`t1_512`.`a1` = `<subquery2>`.`group_concat(b1)`) select left(a1,7), left(a2,7) from t1_512 where a1 in (select group_concat(b1) from t2_512 group by b2); left(a1,7) left(a2,7) set @@group_concat_max_len = 256; explain extended select left(a1,7), left(a2,7) from t1_512 where a1 in (select group_concat(b1) from t2_512 group by b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_512.a1 1 100.00 Using where 2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using filesort Warnings: Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') from `test`.`t2_512` group by `test`.`t2_512`.`b2`) join `test`.`t1_512` where (`test`.`t1_512`.`a1` = `<subquery2>`.`group_concat(b1)`) select left(a1,7), left(a2,7) from t1_512 where a1 in (select group_concat(b1) from t2_512 group by b2); left(a1,7) left(a2,7) drop table t1_512, t2_512, t3_512; set @blob_len = 1024; set @suffix_len = @blob_len - @prefix_len; create table t1_1024 (a1 blob(1024), a2 blob(1024)); create table t2_1024 (b1 blob(1024), b2 blob(1024)); create table t3_1024 (c1 blob(1024), c2 blob(1024)); insert into t1_1024 values (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len))); insert into t1_1024 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t1_1024 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_1024 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t2_1024 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_1024 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); insert into t3_1024 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t3_1024 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t3_1024 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); insert into t3_1024 values (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len))); explain extended select left(a1,7), left(a2,7) from t1_1024 where a1 in (select b1 from t2_1024 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` semi join (`test`.`t2_1024`) where ((`test`.`t2_1024`.`b1` = `test`.`t1_1024`.`a1`) and (`test`.`t1_1024`.`a1` > '0')) select left(a1,7), left(a2,7) from t1_1024 where a1 in (select b1 from t2_1024 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_1024 where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` semi join (`test`.`t2_1024`) where ((`test`.`t2_1024`.`b2` = `test`.`t1_1024`.`a2`) and (`test`.`t2_1024`.`b1` = `test`.`t1_1024`.`a1`) and (`test`.`t1_1024`.`a1` > '0')) select left(a1,7), left(a2,7) from t1_1024 where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_1024 where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 1 PRIMARY <subquery2> eq_ref NULL distinct_key 15 func,func 1 100.00 2 SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where Warnings: Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` semi join (`test`.`t2_1024`) where ((`test`.`t2_1024`.`b1` > '0') and (`test`.`t1_1024`.`a1` = substr(`test`.`t2_1024`.`b1`,1,1024))) select left(a1,7), left(a2,7) from t1_1024 where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0'); left(a1,7) left(a2,7) explain extended select left(a1,7), left(a2,7) from t1_1024 where a1 in (select group_concat(b1) from t2_1024 group by b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_1024.a1 1 100.00 Using where 2 SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using filesort Warnings: Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') from `test`.`t2_1024` group by `test`.`t2_1024`.`b2`) join `test`.`t1_1024` where (`test`.`t1_1024`.`a1` = `<subquery2>`.`group_concat(b1)`) select left(a1,7), left(a2,7) from t1_1024 where a1 in (select group_concat(b1) from t2_1024 group by b2); left(a1,7) left(a2,7) set @@group_concat_max_len = 256; explain extended select left(a1,7), left(a2,7) from t1_1024 where a1 in (select group_concat(b1) from t2_1024 group by b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_1024.a1 1 100.00 Using where 2 SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using filesort Warnings: Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') from `test`.`t2_1024` group by `test`.`t2_1024`.`b2`) join `test`.`t1_1024` where (`test`.`t1_1024`.`a1` = `<subquery2>`.`group_concat(b1)`) select left(a1,7), left(a2,7) from t1_1024 where a1 in (select group_concat(b1) from t2_1024 group by b2); left(a1,7) left(a2,7) drop table t1_1024, t2_1024, t3_1024; set @blob_len = 1025; set @suffix_len = @blob_len - @prefix_len; create table t1_1025 (a1 blob(1025), a2 blob(1025)); create table t2_1025 (b1 blob(1025), b2 blob(1025)); create table t3_1025 (c1 blob(1025), c2 blob(1025)); insert into t1_1025 values (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len))); insert into t1_1025 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t1_1025 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_1025 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t2_1025 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_1025 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); insert into t3_1025 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t3_1025 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t3_1025 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); insert into t3_1025 values (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len))); explain extended select left(a1,7), left(a2,7) from t1_1025 where a1 in (select b1 from t2_1025 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` semi join (`test`.`t2_1025`) where ((`test`.`t2_1025`.`b1` = `test`.`t1_1025`.`a1`) and (`test`.`t1_1025`.`a1` > '0')) select left(a1,7), left(a2,7) from t1_1025 where a1 in (select b1 from t2_1025 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_1025 where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary 1 PRIMARY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` semi join (`test`.`t2_1025`) where ((`test`.`t2_1025`.`b2` = `test`.`t1_1025`.`a2`) and (`test`.`t2_1025`.`b1` = `test`.`t1_1025`.`a1`) and (`test`.`t1_1025`.`a1` > '0')) select left(a1,7), left(a2,7) from t1_1025 where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x 1 - 02x 2 - 02x explain extended select left(a1,7), left(a2,7) from t1_1025 where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0'); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 1 PRIMARY <subquery2> eq_ref NULL distinct_key 15 func,func 1 100.00 2 SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where Warnings: Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` semi join (`test`.`t2_1025`) where ((`test`.`t2_1025`.`b1` > '0') and (`test`.`t1_1025`.`a1` = substr(`test`.`t2_1025`.`b1`,1,1025))) select left(a1,7), left(a2,7) from t1_1025 where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0'); left(a1,7) left(a2,7) explain extended select left(a1,7), left(a2,7) from t1_1025 where a1 in (select group_concat(b1) from t2_1025 group by b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_1025.a1 1 100.00 Using where 2 SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using filesort Warnings: Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') from `test`.`t2_1025` group by `test`.`t2_1025`.`b2`) join `test`.`t1_1025` where (`test`.`t1_1025`.`a1` = `<subquery2>`.`group_concat(b1)`) select left(a1,7), left(a2,7) from t1_1025 where a1 in (select group_concat(b1) from t2_1025 group by b2); left(a1,7) left(a2,7) set @@group_concat_max_len = 256; explain extended select left(a1,7), left(a2,7) from t1_1025 where a1 in (select group_concat(b1) from t2_1025 group by b2); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_1025.a1 1 100.00 Using where 2 SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using filesort Warnings: Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') from `test`.`t2_1025` group by `test`.`t2_1025`.`b2`) join `test`.`t1_1025` where (`test`.`t1_1025`.`a1` = `<subquery2>`.`group_concat(b1)`) select left(a1,7), left(a2,7) from t1_1025 where a1 in (select group_concat(b1) from t2_1025 group by b2); left(a1,7) left(a2,7) drop table t1_1025, t2_1025, t3_1025; create table t1bit (a1 bit(3), a2 bit(3)); create table t2bit (b1 bit(3), b2 bit(3)); insert into t1bit values (b'000', b'100'); insert into t1bit values (b'001', b'101'); insert into t1bit values (b'010', b'110'); insert into t2bit values (b'001', b'101'); insert into t2bit values (b'010', b'110'); insert into t2bit values (b'110', b'111'); explain extended select bin(a1), bin(a2) from t1bit where (a1, a2) in (select b1, b2 from t2bit); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1bit ALL NULL NULL NULL NULL 3 100.00 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 10 func,func 1 100.00 2 SUBQUERY t2bit ALL NULL NULL NULL NULL 3 100.00 Warnings: Note 1003 select conv(`test`.`t1bit`.`a1`,10,2) AS `bin(a1)`,conv(`test`.`t1bit`.`a2`,10,2) AS `bin(a2)` from `test`.`t1bit` semi join (`test`.`t2bit`) where 1 select bin(a1), bin(a2) from t1bit where (a1, a2) in (select b1, b2 from t2bit); bin(a1) bin(a2) 1 101 10 110 drop table t1bit, t2bit; create table t1bb (a1 bit(3), a2 blob(3)); create table t2bb (b1 bit(3), b2 blob(3)); insert into t1bb values (b'000', '100'); insert into t1bb values (b'001', '101'); insert into t1bb values (b'010', '110'); insert into t2bb values (b'001', '101'); insert into t2bb values (b'010', '110'); insert into t2bb values (b'110', '111'); explain extended select bin(a1), a2 from t1bb where (a1, a2) in (select b1, b2 from t2bb); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1bb ALL NULL NULL NULL NULL 3 100.00 Start temporary 1 PRIMARY t2bb ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join) Warnings: Note 1003 select conv(`test`.`t1bb`.`a1`,10,2) AS `bin(a1)`,`test`.`t1bb`.`a2` AS `a2` from `test`.`t1bb` semi join (`test`.`t2bb`) where ((`test`.`t2bb`.`b2` = `test`.`t1bb`.`a2`) and (`test`.`t2bb`.`b1` = `test`.`t1bb`.`a1`)) select bin(a1), a2 from t1bb where (a1, a2) in (select b1, b2 from t2bb); bin(a1) a2 1 101 10 110 drop table t1bb, t2bb; drop table t1, t2, t3, t1i, t2i, t3i, columns; /****************************************************************************** * Test the cache of the left operand of IN. ******************************************************************************/ # Test that default values of Cached_item are not used for comparison create table t1 (s1 int); create table t2 (s2 int); insert into t1 values (5),(1),(0); insert into t2 values (0), (1); select s2 from t2 where s2 in (select s1 from t1); s2 0 1 drop table t1, t2; create table t1 (a int not null, b int not null); create table t2 (c int not null, d int not null); create table t3 (e int not null); insert into t1 values (1,10); insert into t1 values (1,20); insert into t1 values (2,10); insert into t1 values (2,20); insert into t1 values (2,30); insert into t1 values (3,20); insert into t1 values (4,40); insert into t2 values (2,10); insert into t2 values (2,20); insert into t2 values (2,40); insert into t2 values (3,20); insert into t2 values (4,10); insert into t2 values (5,10); insert into t3 values (10); insert into t3 values (10); insert into t3 values (20); insert into t3 values (30); explain extended select a from t1 where a in (select c from t2 where d >= 20); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY <subquery2> ALL distinct_key NULL NULL NULL 6 100.00 1 PRIMARY t1 ALL NULL NULL NULL NULL 7 100.00 Using where; Using join buffer (flat, BNL join) 2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t1`.`a` = `test`.`t2`.`c`) and (`test`.`t2`.`d` >= 20)) select a from t1 where a in (select c from t2 where d >= 20); a 2 2 2 3 create index it1a on t1(a); explain extended select a from t1 where a in (select c from t2 where d >= 20); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY <subquery2> ALL distinct_key NULL NULL NULL 6 100.00 1 PRIMARY t1 ref it1a it1a 4 test.t2.c 2 100.00 Using index 2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t1`.`a` = `test`.`t2`.`c`) and (`test`.`t2`.`d` >= 20)) select a from t1 where a in (select c from t2 where d >= 20); a 2 2 2 3 insert into t2 values (1,10); explain extended select a from t1 where a in (select c from t2 where d >= 20); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 index it1a it1a 4 NULL 7 100.00 Using index 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 4 func 1 100.00 2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`d` >= 20)) select a from t1 where a in (select c from t2 where d >= 20); a 2 2 2 3 explain extended select a from t1 group by a having a in (select c from t2 where d >= 20); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 index NULL it1a 4 NULL 7 100.00 Using index 2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where ((`test`.`t1`.`a` = `<subquery2>`.`c`)))))) select a from t1 group by a having a in (select c from t2 where d >= 20); a 2 3 create index iab on t1(a, b); explain extended select a from t1 group by a having a in (select c from t2 where d >= 20); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 index NULL it1a 4 NULL 7 100.00 Using index 2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where ((`test`.`t1`.`a` = `<subquery2>`.`c`)))))) select a from t1 group by a having a in (select c from t2 where d >= 20); a 2 3 explain extended select a from t1 group by a having a in (select c from t2 where d >= some(select e from t3 where max(b)=e)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 index NULL iab 8 NULL 7 100.00 Using index 2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where 3 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Note 1276 Field or reference 'test.t1.b' of SELECT #3 was resolved in SELECT #1 Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`,max(`test`.`t1`.`b`)>(<in_optimizer>(`test`.`t1`.`a`,<exists>(select `test`.`t2`.`c` from `test`.`t2` where (<nop>(<expr_cache><`test`.`t2`.`d`,max(`test`.`t1`.`b`)>(<in_optimizer>(`test`.`t2`.`d`,<exists>(select `test`.`t3`.`e` from `test`.`t3` where (max(`test`.`t1`.`b`) = `test`.`t3`.`e`) having (<cache>(`test`.`t2`.`d`) >= <ref_null_helper>(`test`.`t3`.`e`)))))) and (<cache>(`test`.`t1`.`a`) = `test`.`t2`.`c`))))) select a from t1 group by a having a in (select c from t2 where d >= some(select e from t3 where max(b)=e)); a 2 3 explain extended select a from t1 where a in (select c from t2 where d >= some(select e from t3 where b=e)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t2 ALL NULL NULL NULL NULL 7 100.00 Start temporary 1 PRIMARY t1 ref it1a,iab iab 4 test.t2.c 1 100.00 Using where; Using index; End temporary 3 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Note 1276 Field or reference 'test.t1.b' of SELECT #3 was resolved in SELECT #1 Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t1`.`a` = `test`.`t2`.`c`) and <nop>(<expr_cache><`test`.`t2`.`d`,`test`.`t1`.`b`>(<in_optimizer>(`test`.`t2`.`d`,<exists>(select `test`.`t3`.`e` from `test`.`t3` where ((`test`.`t1`.`b` = `test`.`t3`.`e`) and (<cache>(`test`.`t2`.`d`) >= `test`.`t3`.`e`))))))) select a from t1 where a in (select c from t2 where d >= some(select e from t3 where b=e)); a 2 2 2 3 1 drop table t1, t2, t3; create table t2 (a int, b int, key(a), key(b)); insert into t2 values (3,3),(3,3),(3,3); select 1 from t2 where t2.a > 1 or t2.a = 3 and not t2.a not in (select t2.b from t2); 1 1 1 1 drop table t2; create table t1 (a1 int key); create table t2 (b1 int); insert into t1 values (5); explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 system NULL NULL NULL NULL 1 1 PRIMARY <subquery2> const distinct_key distinct_key 5 const 1 2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL no matching row in const table select min(a1) from t1 where 7 in (select b1 from t2 group by b1); min(a1) NULL set @save_optimizer_switch=@@optimizer_switch; set @@optimizer_switch='default,materialization=off'; explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Select tables optimized away 2 DEPENDENT SUBQUERY t2 system NULL NULL NULL NULL 0 const row not found select min(a1) from t1 where 7 in (select b1 from t2 group by b1); min(a1) set @@optimizer_switch='default,semijoin=off'; explain select min(a1) from t1 where 7 in (select b1 from t2); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Select tables optimized away 2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables select min(a1) from t1 where 7 in (select b1 from t2); min(a1) set @@optimizer_switch='default,materialization=off'; # with MariaDB and MWL#90, this particular case is solved: explain select min(a1) from t1 where 7 in (select b1 from t2); 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 select min(a1) from t1 where 7 in (select b1 from t2); min(a1) NULL # but when we go around MWL#90 code, the problem still shows up: explain select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Select tables optimized away 2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4; min(a1) set @@optimizer_switch= @save_optimizer_switch; drop table t1,t2; create table t1 (a char(2), b varchar(10)); insert into t1 values ('a', 'aaa'); insert into t1 values ('aa', 'aaaa'); explain select a,b from t1 where b in (select a from t1); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 2 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 3 func 1 2 SUBQUERY t1 ALL NULL NULL NULL NULL 2 select a,b from t1 where b in (select a from t1); a b prepare st1 from "select a,b from t1 where b in (select a from t1)"; execute st1; a b execute st1; a b drop table t1; CREATE TABLE t1 (f1 INT, f2 DECIMAL(5,3)) ENGINE=MyISAM; INSERT INTO t1 (f1, f2) VALUES (1, 1.789); INSERT INTO t1 (f1, f2) VALUES (13, 1.454); INSERT INTO t1 (f1, f2) VALUES (10, 1.668); CREATE TABLE t2 LIKE t1; INSERT INTO t2 VALUES (1, 1.789); INSERT INTO t2 VALUES (13, 1.454); set @save_optimizer_switch=@@optimizer_switch; SET @@optimizer_switch='default,semijoin=on,materialization=on'; EXPLAIN SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY <subquery2> ALL distinct_key NULL NULL NULL 2 1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 2 SUBQUERY t2 ALL NULL NULL NULL NULL 2 SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2); COUNT(*) 2 set @@optimizer_switch= @save_optimizer_switch; DROP TABLE t1, t2; CREATE TABLE t1 ( pk int, a varchar(1), b varchar(4), c varchar(4), d varchar(4), PRIMARY KEY (pk) ); INSERT INTO t1 VALUES (1,'o','ffff','ffff','ffoo'),(2,'f','ffff','ffff','ffff'); CREATE TABLE t2 LIKE t1; INSERT INTO t2 VALUES (1,'i','iiii','iiii','iiii'),(2,'f','ffff','ffff','ffff'); set @save_optimizer_switch=@@optimizer_switch; SET @@optimizer_switch='default,semijoin=on,materialization=on'; EXPLAIN SELECT pk FROM t1 WHERE (a) IN (SELECT a FROM t2 WHERE pk > 0); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 2 1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 5 func 1 2 SUBQUERY t2 range PRIMARY PRIMARY 4 NULL 2 Using index condition; Rowid-ordered scan SELECT pk FROM t1 WHERE (a) IN (SELECT a FROM t2 WHERE pk > 0); pk 2 SELECT pk FROM t1 WHERE (b,c,d) IN (SELECT b,c,d FROM t2 WHERE pk > 0); pk 2 DROP TABLE t1, t2; set optimizer_switch=@save_optimizer_switch; # # BUG#50019: Wrong result for IN-subquery with materialization # create table t1(i int); insert into t1 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10); create table t2(i int); insert into t2 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10); create table t3(i int); insert into t3 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10); select * from t1 where t1.i in (select t2.i from t2 join t3 where t2.i + t3.i = 5); i 1 2 3 4 set @save_optimizer_switch=@@optimizer_switch; set session optimizer_switch='materialization=off,in_to_exists=on'; select * from t1 where t1.i in (select t2.i from t2 join t3 where t2.i + t3.i = 5); i 4 3 2 1 set session optimizer_switch=@save_optimizer_switch; drop table t1, t2, t3; create table t0 (a int); insert into t0 values (0),(1),(2); create table t1 (a int); insert into t1 values (0),(1),(2); explain select a, a in (select a from t1) from t0; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t0 ALL NULL NULL NULL NULL 3 2 SUBQUERY t1 ALL NULL NULL NULL NULL 3 select a, a in (select a from t1) from t0; a a in (select a from t1) 0 1 1 1 2 1 prepare s from 'select a, a in (select a from t1) from t0'; execute s; a a in (select a from t1) 0 1 1 1 2 1 update t1 set a=123; execute s; a a in (select a from t1) 0 0 1 0 2 0 drop table t0, t1; set optimizer_switch='firstmatch=on'; # # MWL#90, review feedback: check what happens when the subquery # looks like candidate for MWL#90 checking at the first glance # but then subselect_hash_sj_engine::init_permanent() discovers # that it's not possible to perform duplicate removal for the # selected datatypes, and so materialization isn't applicable after # all. # set @blob_len = 1024; set @suffix_len = @blob_len - @prefix_len; create table t1_1024 (a1 blob(1024), a2 blob(1024)); create table t2_1024 (b1 blob(1024), b2 blob(1024)); insert into t1_1024 values (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len))); insert into t1_1024 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t1_1024 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_1024 values (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len))); insert into t2_1024 values (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len))); insert into t2_1024 values (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len))); explain select left(a1,7), left(a2,7) from t1_1024 where (a1,3) in (select substring(b1,1,1024), count(*) from t2_1024 where b1 > '0'); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 Using where 2 DEPENDENT SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 Using where select left(a1,7), left(a2,7) from t1_1024 where (a1,3) in (select substring(b1,1,1024), count(*) from t2_1024 where b1 > '0'); left(a1,7) left(a2,7) 1 - 01x 2 - 01x drop table t1_1024, t2_1024;