create table t1 (a int, b int) engine=MyISAM; create table t2 (c int, d int) engine=MyISAM; insert into t1 values (1,1),(2,2),(3,3),(2,2); insert into t2 values (2,2),(2,2),(5,5); select * from t1 intersect all select * from t2; a b 2 2 2 2 (select a,b from t1) intersect all (select c,d from t2); a b 2 2 2 2 select * from ((select a,b from t1) intersect all (select c,d from t2)) t; a b 2 2 2 2 select * from ((select a from t1) intersect all (select c from t2)) t; a 2 2 drop tables t1,t2; create table t1 (a int, b int) engine=MyISAM; create table t2 (c int, d int) engine=MyISAM; create table t3 (e int, f int) engine=MyISAM; insert into t1 values (1,1),(2,2),(3,3),(2,2); insert into t2 values (2,2),(3,3),(4,4),(2,2); insert into t3 values (1,1),(2,2),(5,5),(2,2); (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3); a b 2 2 2 2 EXPLAIN (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 4 2 INTERSECT t2 ALL NULL NULL NULL NULL 4 3 INTERSECT t3 ALL NULL NULL NULL NULL 4 NULL INTERSECT RESULT ALL NULL NULL NULL NULL NULL EXPLAIN extended (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 4 100.00 2 INTERSECT t2 ALL NULL NULL NULL NULL 4 100.00 3 INTERSECT t3 ALL NULL NULL NULL NULL 4 100.00 NULL INTERSECT RESULT ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 (/* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1`) intersect all (/* select#2 */ select `test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2`) intersect all (/* select#3 */ select `test`.`t3`.`e` AS `e`,`test`.`t3`.`f` AS `f` from `test`.`t3`) EXPLAIN extended select * from ((select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3)) a; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY ALL NULL NULL NULL NULL 4 100.00 2 DERIVED t1 ALL NULL NULL NULL NULL 4 100.00 3 INTERSECT t2 ALL NULL NULL NULL NULL 4 100.00 4 INTERSECT t3 ALL NULL NULL NULL NULL 4 100.00 NULL INTERSECT RESULT ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 /* select#1 */ select `a`.`a` AS `a`,`a`.`b` AS `b` from ((/* select#2 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1`) intersect all (/* select#3 */ select `test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2`) intersect all (/* select#4 */ select `test`.`t3`.`e` AS `e`,`test`.`t3`.`f` AS `f` from `test`.`t3`)) `a` EXPLAIN format=json (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3); EXPLAIN { "query_block": { "union_result": { "table_name": "", "access_type": "ALL", "query_specifications": [ { "query_block": { "select_id": 1, "table": { "table_name": "t1", "access_type": "ALL", "rows": 4, "filtered": 100 } } }, { "query_block": { "select_id": 2, "operation": "INTERSECT", "table": { "table_name": "t2", "access_type": "ALL", "rows": 4, "filtered": 100 } } }, { "query_block": { "select_id": 3, "operation": "INTERSECT", "table": { "table_name": "t3", "access_type": "ALL", "rows": 4, "filtered": 100 } } } ] } } } ANALYZE format=json (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3); ANALYZE { "query_block": { "union_result": { "table_name": "", "access_type": "ALL", "r_loops": 1, "r_rows": 2, "query_specifications": [ { "query_block": { "select_id": 1, "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t1", "access_type": "ALL", "r_loops": 1, "rows": 4, "r_rows": 4, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 } } }, { "query_block": { "select_id": 2, "operation": "INTERSECT", "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t2", "access_type": "ALL", "r_loops": 1, "rows": 4, "r_rows": 4, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 } } }, { "query_block": { "select_id": 3, "operation": "INTERSECT", "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t3", "access_type": "ALL", "r_loops": 1, "rows": 4, "r_rows": 4, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 } } } ] } } } ANALYZE format=json select * from ((select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3)) a; ANALYZE { "query_block": { "select_id": 1, "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "", "access_type": "ALL", "r_loops": 1, "rows": 4, "r_rows": 2, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100, "materialized": { "query_block": { "union_result": { "table_name": "", "access_type": "ALL", "r_loops": 1, "r_rows": 2, "query_specifications": [ { "query_block": { "select_id": 2, "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t1", "access_type": "ALL", "r_loops": 1, "rows": 4, "r_rows": 4, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 } } }, { "query_block": { "select_id": 3, "operation": "INTERSECT", "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t2", "access_type": "ALL", "r_loops": 1, "rows": 4, "r_rows": 4, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 } } }, { "query_block": { "select_id": 4, "operation": "INTERSECT", "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t3", "access_type": "ALL", "r_loops": 1, "rows": 4, "r_rows": 4, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 } } } ] } } } } } } select * from ((select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3)) a; a b 2 2 2 2 prepare stmt from "(select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3);"; execute stmt; a b 2 2 2 2 execute stmt; a b 2 2 2 2 prepare stmt from "select * from ((select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3)) a"; execute stmt; a b 2 2 2 2 execute stmt; a b 2 2 2 2 insert into t1 values (2,2),(3,3); insert into t2 values (2,2),(2,2),(2,2); (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3); a b 2 2 2 2 (select a,b from t1) intersect (select c,d from t2) intersect all (select e,f from t3); a b 2 2 insert into t3 values (2,2); (select a,b from t1) intersect all (select c,d from t2) intersect (select e,f from t3); a b 2 2 (select a,b from t1) intersect all (select c,e from t2,t3); a b 2 2 2 2 2 2 EXPLAIN (select a,b from t1) intersect all (select c,e from t2,t3); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 6 2 INTERSECT t3 ALL NULL NULL NULL NULL 5 2 INTERSECT t2 ALL NULL NULL NULL NULL 7 Using join buffer (flat, BNL join) NULL INTERSECT RESULT ALL NULL NULL NULL NULL NULL EXPLAIN extended (select a,b from t1) intersect all (select c,e from t2,t3); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 6 100.00 2 INTERSECT t3 ALL NULL NULL NULL NULL 5 100.00 2 INTERSECT t2 ALL NULL NULL NULL NULL 7 100.00 Using join buffer (flat, BNL join) NULL INTERSECT RESULT ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 (/* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1`) intersect all (/* select#2 */ select `test`.`t2`.`c` AS `c`,`test`.`t3`.`e` AS `e` from `test`.`t2` join `test`.`t3`) EXPLAIN extended select * from ((select a,b from t1) intersect all (select c,e from t2,t3)) a; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY ALL NULL NULL NULL NULL 6 100.00 2 DERIVED t1 ALL NULL NULL NULL NULL 6 100.00 3 INTERSECT t3 ALL NULL NULL NULL NULL 5 100.00 3 INTERSECT t2 ALL NULL NULL NULL NULL 7 100.00 Using join buffer (flat, BNL join) NULL INTERSECT RESULT ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 /* select#1 */ select `a`.`a` AS `a`,`a`.`b` AS `b` from ((/* select#2 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1`) intersect all (/* select#3 */ select `test`.`t2`.`c` AS `c`,`test`.`t3`.`e` AS `e` from `test`.`t2` join `test`.`t3`)) `a` EXPLAIN format=json (select a,b from t1) intersect all (select c,e from t2,t3); EXPLAIN { "query_block": { "union_result": { "table_name": "", "access_type": "ALL", "query_specifications": [ { "query_block": { "select_id": 1, "table": { "table_name": "t1", "access_type": "ALL", "rows": 6, "filtered": 100 } } }, { "query_block": { "select_id": 2, "operation": "INTERSECT", "table": { "table_name": "t3", "access_type": "ALL", "rows": 5, "filtered": 100 }, "block-nl-join": { "table": { "table_name": "t2", "access_type": "ALL", "rows": 7, "filtered": 100 }, "buffer_type": "flat", "buffer_size": "65", "join_type": "BNL" } } } ] } } } ANALYZE format=json (select a,b from t1) intersect all (select c,e from t2,t3); ANALYZE { "query_block": { "union_result": { "table_name": "", "access_type": "ALL", "r_loops": 1, "r_rows": 3, "query_specifications": [ { "query_block": { "select_id": 1, "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t1", "access_type": "ALL", "r_loops": 1, "rows": 6, "r_rows": 6, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 } } }, { "query_block": { "select_id": 2, "operation": "INTERSECT", "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t3", "access_type": "ALL", "r_loops": 1, "rows": 5, "r_rows": 5, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 }, "block-nl-join": { "table": { "table_name": "t2", "access_type": "ALL", "r_loops": 1, "rows": 7, "r_rows": 7, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 }, "buffer_type": "flat", "buffer_size": "65", "join_type": "BNL", "r_filtered": 100 } } } ] } } } ANALYZE format=json select * from ((select a,b from t1) intersect all (select c,e from t2,t3)) a; ANALYZE { "query_block": { "select_id": 1, "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "", "access_type": "ALL", "r_loops": 1, "rows": 6, "r_rows": 3, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100, "materialized": { "query_block": { "union_result": { "table_name": "", "access_type": "ALL", "r_loops": 1, "r_rows": 3, "query_specifications": [ { "query_block": { "select_id": 2, "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t1", "access_type": "ALL", "r_loops": 1, "rows": 6, "r_rows": 6, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 } } }, { "query_block": { "select_id": 3, "operation": "INTERSECT", "r_loops": 1, "r_total_time_ms": "REPLACED", "table": { "table_name": "t3", "access_type": "ALL", "r_loops": 1, "rows": 5, "r_rows": 5, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 }, "block-nl-join": { "table": { "table_name": "t2", "access_type": "ALL", "r_loops": 1, "rows": 7, "r_rows": 7, "r_table_time_ms": "REPLACED", "r_other_time_ms": "REPLACED", "filtered": 100, "r_filtered": 100 }, "buffer_type": "flat", "buffer_size": "65", "join_type": "BNL", "r_filtered": 100 } } } ] } } } } } } select * from ((select a,b from t1) intersect all (select c,e from t2,t3)) a; a b 2 2 2 2 2 2 prepare stmt from "(select a,b from t1) intersect all (select c,e from t2,t3);"; execute stmt; a b 2 2 2 2 2 2 execute stmt; a b 2 2 2 2 2 2 prepare stmt from "select * from ((select a,b from t1) intersect all (select c,e from t2,t3)) a"; execute stmt; a b 2 2 2 2 2 2 execute stmt; a b 2 2 2 2 2 2 drop tables t1,t2,t3; select 1 as a from dual intersect all select 1 from dual; a 1 (select 1 from dual) intersect all (select 1 from dual); 1 1 (select 1 from dual into @v) intersect all (select 1 from dual); ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'into @v) intersect all (select 1 from dual)' at line 1 select 1 from dual ORDER BY 1 intersect all select 1 from dual; ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'intersect all select 1 from dual' at line 1 select 1 as a from dual union all select 1 from dual; a 1 1 create table t1 (a int, b blob, a1 int, b1 blob); create table t2 (c int, d blob, c1 int, d1 blob); insert into t1 values (1,"ddd", 1, "sdfrrwwww"),(2, "fgh", 2, "dffggtt"),(2, "fgh", 2, "dffggtt"); insert into t2 values (2, "fgh", 2, "dffggtt"),(3, "ffggddd", 3, "dfgg"),(2, "fgh", 2, "dffggtt"); (select a,b,b1 from t1) intersect all (select c,d,d1 from t2); a b b1 2 fgh dffggtt 2 fgh dffggtt drop tables t1,t2; create table t1 (a int, b blob) engine=MyISAM; create table t2 (c int, d blob) engine=MyISAM; create table t3 (e int, f blob) engine=MyISAM; insert into t1 values (1,1),(2,2),(3,3),(2,2),(3,3); insert into t2 values (2,2),(3,3),(4,4),(2,2),(2,2),(2,2); insert into t3 values (1,1),(2,2),(5,5),(2,2),(5,5); (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3); a b 2 2 2 2 select * from ((select a,b from t1) intersect all (select c,d from t2) intersect (select e,f from t3)) a; a b 2 2 prepare stmt from "(select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3);"; execute stmt; a b 2 2 2 2 execute stmt; a b 2 2 2 2 prepare stmt from "select * from ((select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3)) a"; execute stmt; a b 2 2 2 2 execute stmt; a b 2 2 2 2 create table t4 (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3); show create table t4; Table Create Table t4 CREATE TABLE `t4` ( `a` int(11) DEFAULT NULL, `b` blob DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 drop tables t4; (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4); a b 4 4 2 2 2 2 (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4) except all (select 2,2); a b 4 4 2 2 drop tables t1,t2,t3; create table t1 (a int, b int); create table t2 (c int, d int); create table t3 (e int, f int); insert into t1 values (1,1),(2,2),(3,3),(2,2),(3,3); insert into t2 values (2,2),(3,3),(4,4),(2,2),(2,2),(2,2); insert into t3 values (1,1),(2,2),(5,5),(2,2),(5,5); (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4); a b 4 4 2 2 2 2 (select a,b from t1) intersect all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4) except all (select 2,2); a b 4 4 2 2 drop tables t1,t2,t3; # # INTERSECT precedence # create table t1 (a int, b blob) engine=MyISAM; create table t2 (c int, d blob) engine=MyISAM; create table t3 (e int, f blob) engine=MyISAM; insert into t1 values (5,5),(6,6); insert into t2 values (2,2),(3,3); insert into t3 values (1,1),(3,3); (select a,b from t1) union all (select c,d from t2) intersect (select e,f from t3) union all (select 4,4); a b 5 5 6 6 3 3 4 4 (select a,b from t1) union all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4); a b 5 5 6 6 3 3 4 4 explain extended (select a,b from t1) union all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 2 100.00 5 UNION ALL NULL NULL NULL NULL 2 100.00 2 DERIVED t2 ALL NULL NULL NULL NULL 2 100.00 3 INTERSECT t3 ALL NULL NULL NULL NULL 2 100.00 NULL INTERSECT RESULT ALL NULL NULL NULL NULL NULL NULL 4 UNION NULL NULL NULL NULL NULL NULL NULL NULL No tables used Warnings: Note 1003 (/* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1`) union all /* select#5 */ select `__5`.`c` AS `c`,`__5`.`d` AS `d` from ((/* select#2 */ select `test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2`) intersect all (/* select#3 */ select `test`.`t3`.`e` AS `e`,`test`.`t3`.`f` AS `f` from `test`.`t3`)) `__5` union all (/* select#4 */ select 4 AS `4`,4 AS `4`) insert into t2 values (3,3); insert into t3 values (3,3); (select e,f from t3) intersect all (select c,d from t2) union all (select a,b from t1) union all (select 4,4); e f 3 3 3 3 5 5 6 6 4 4 explain extended (select e,f from t3) intersect all (select c,d from t2) union all (select a,b from t1) union all (select 4,4); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 3 100.00 2 INTERSECT t2 ALL NULL NULL NULL NULL 3 100.00 3 UNION t1 ALL NULL NULL NULL NULL 2 100.00 4 UNION NULL NULL NULL NULL NULL NULL NULL NULL No tables used NULL UNIT RESULT ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 (/* select#1 */ select `test`.`t3`.`e` AS `e`,`test`.`t3`.`f` AS `f` from `test`.`t3`) intersect all (/* select#2 */ select `test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2`) union all (/* select#3 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1`) union all (/* select#4 */ select 4 AS `4`,4 AS `4`) (/* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1`) union /* select#3 */ select `__3`.`c` AS `c`,`__3`.`d` AS `d` from ((/* select#2 */ select `test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2`) intersect all (/* select#4 */ select `test`.`t3`.`e` AS `e`,`test`.`t3`.`f` AS `f` from `test`.`t3`)) `__3` union (/* select#5 */ select 4 AS `4`,4 AS `4`); a b 5 5 6 6 3 3 4 4 prepare stmt from "(select a,b from t1) union all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4)"; execute stmt; a b 5 5 6 6 3 3 3 3 4 4 execute stmt; a b 5 5 6 6 3 3 3 3 4 4 create view v1 as (select a,b from t1) union all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4); select b,a,b+1 from v1; b a b+1 5 5 6 6 6 7 3 3 4 3 3 4 4 4 5 select b,a,b+1 from v1 where a > 3; b a b+1 5 5 6 6 6 7 4 4 5 create procedure p1() select * from v1; call p1(); a b 5 5 6 6 3 3 3 3 4 4 call p1(); a b 5 5 6 6 3 3 3 3 4 4 drop procedure p1; create procedure p1() (select a,b from t1) union all (select c,d from t2) intersect all (select e,f from t3) union all (select 4,4); call p1(); a b 5 5 6 6 3 3 3 3 4 4 call p1(); a b 5 5 6 6 3 3 3 3 4 4 drop procedure p1; show create view v1; View Create View character_set_client collation_connection v1 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v1` AS (select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1`) union all select `__6`.`c` AS `c`,`__6`.`d` AS `d` from ((select `test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2`) intersect all (select `test`.`t3`.`e` AS `e`,`test`.`t3`.`f` AS `f` from `test`.`t3`)) `__6` union all (select 4 AS `4`,4 AS `4`) latin1 latin1_swedish_ci drop view v1; drop tables t1,t2,t3; CREATE TABLE t (i INT); INSERT INTO t VALUES (1),(2); SELECT * FROM t WHERE i != ANY ( SELECT 6 INTERSECT ALL SELECT 3 ); i select i from t where exists ((select 6 as r from dual having t.i <> 6) intersect all (select 3 from dual having t.i <> 3)); i drop table t; CREATE TABLE t1 (a varchar(32)) ENGINE=MyISAM; INSERT INTO t1 VALUES ('Jakarta'),('Lisbon'),('Honolulu'),('Lusaka'),('Barcelona'),('Taipei'), ('Brussels'),('Orlando'),('Osaka'),('Quito'),('Lima'),('Tunis'), ('Unalaska'),('Rotterdam'),('Zagreb'),('Ufa'),('Ryazan'),('Xiamen'), ('London'),('Izmir'),('Samara'),('Bern'),('Zhengzhou'),('Vladivostok'), ('Yangon'),('Victoria'),('Warsaw'),('Luanda'),('Leon'),('Bangkok'), ('Wellington'),('Zibo'),('Qiqihar'),('Delhi'),('Hamburg'),('Ottawa'), ('Vaduz'); CREATE TABLE t2 (b varchar(32)) ENGINE=MyISAM; INSERT INTO t2 VALUES ('Gaza'),('Jeddah'),('Beirut'),('Incheon'),('Tbilisi'),('Izmir'), ('Quito'),('Riga'),('Freetown'),('Zagreb'),('Caracas'),('Orlando'), ('Kingston'),('Turin'),('Xinyang'),('Osaka'),('Albany'),('Geneva'), ('Omsk'),('Kazan'),('Quezon'),('Indore'),('Odessa'),('Xiamen'), ('Winnipeg'),('Yakutsk'),('Nairobi'),('Ufa'),('Helsinki'),('Vilnius'), ('Aden'),('Liverpool'),('Honolulu'),('Frankfurt'),('Glasgow'), ('Vienna'),('Jackson'),('Jakarta'),('Sydney'),('Oslo'),('Novgorod'), ('Norilsk'),('Izhevsk'),('Istanbul'),('Nice'); CREATE TABLE t3 (c varchar(32)) ENGINE=MyISAM; INSERT INTO t3 VALUES ('Nicosia'),('Istanbul'),('Richmond'),('Stockholm'),('Dublin'), ('Wichita'),('Warsaw'),('Glasgow'),('Winnipeg'),('Irkutsk'),('Quito'), ('Xiamen'),('Berlin'),('Rome'),('Denver'),('Dallas'),('Kabul'), ('Prague'),('Izhevsk'),('Tirana'),('Sofia'),('Detroit'),('Sorbonne'); select count(*) from ( SELECT * FROM t1 LEFT OUTER JOIN t2 LEFT OUTER JOIN t3 ON b < c ON a > b INTERSECT SELECT * FROM t1 LEFT OUTER JOIN t2 LEFT OUTER JOIN t3 ON b < c ON a > b ) a; count(*) 14848 select count(*) from ( SELECT * FROM t1 LEFT OUTER JOIN t2 LEFT OUTER JOIN t3 ON b < c ON a > b INTERSECT ALL SELECT * FROM t1 LEFT OUTER JOIN t2 LEFT OUTER JOIN t3 ON b < c ON a > b ) a; count(*) 14848 insert into t1 values ('Xiamen'); insert into t2 values ('Xiamen'),('Xiamen'); insert into t3 values ('Xiamen'); select count(*) from ( SELECT * FROM t1 LEFT OUTER JOIN t2 LEFT OUTER JOIN t3 ON b < c ON a > b INTERSECT ALL SELECT * FROM t1 LEFT OUTER JOIN t2 LEFT OUTER JOIN t3 ON b < c ON a > b ) a; count(*) 16430 drop table t1,t2,t3; CREATE TABLE t1 (a varchar(32) not null) ENGINE=MyISAM; INSERT INTO t1 VALUES ('Jakarta'),('Lisbon'),('Honolulu'),('Lusaka'),('Barcelona'),('Taipei'), ('Brussels'),('Orlando'),('Osaka'),('Quito'),('Lima'),('Tunis'), ('Unalaska'),('Rotterdam'),('Zagreb'),('Ufa'),('Ryazan'),('Xiamen'), ('London'),('Izmir'),('Samara'),('Bern'),('Zhengzhou'),('Vladivostok'), ('Yangon'),('Victoria'),('Warsaw'),('Luanda'),('Leon'),('Bangkok'), ('Wellington'),('Zibo'),('Qiqihar'),('Delhi'),('Hamburg'),('Ottawa'), ('Vaduz'),('Detroit'),('Detroit'); CREATE TABLE t2 (b varchar(32) not null) ENGINE=MyISAM; INSERT INTO t2 VALUES ('Gaza'),('Jeddah'),('Beirut'),('Incheon'),('Tbilisi'),('Izmir'), ('Quito'),('Riga'),('Freetown'),('Zagreb'),('Caracas'),('Orlando'), ('Kingston'),('Turin'),('Xinyang'),('Osaka'),('Albany'),('Geneva'), ('Omsk'),('Kazan'),('Quezon'),('Indore'),('Odessa'),('Xiamen'), ('Winnipeg'),('Yakutsk'),('Nairobi'),('Ufa'),('Helsinki'),('Vilnius'), ('Aden'),('Liverpool'),('Honolulu'),('Frankfurt'),('Glasgow'), ('Vienna'),('Jackson'),('Jakarta'),('Sydney'),('Oslo'),('Novgorod'), ('Norilsk'),('Izhevsk'),('Istanbul'),('Nice'),('Detroit'),('Detroit'); CREATE TABLE t3 (c varchar(32) not null) ENGINE=MyISAM; INSERT INTO t3 VALUES ('Nicosia'),('Istanbul'),('Richmond'),('Stockholm'),('Dublin'), ('Wichita'),('Warsaw'),('Glasgow'),('Winnipeg'),('Irkutsk'),('Quito'), ('Xiamen'),('Berlin'),('Rome'),('Denver'),('Dallas'),('Kabul'), ('Prague'),('Izhevsk'),('Tirana'),('Sofia'),('Detroit'),('Sorbonne'), ('Detroit'); select count(*) from ( SELECT * FROM t1 LEFT OUTER JOIN t2 LEFT OUTER JOIN t3 ON b < c ON a > b INTERSECT SELECT * FROM t1 LEFT OUTER JOIN t2 LEFT OUTER JOIN t3 ON b < c ON a > b ) a; count(*) 15547 drop table t1,t2,t3; create table t12(c1 int); insert into t12 values(1); insert into t12 values(2); create table t13(c1 int); insert into t13 values(1); insert into t13 values(3); create table t234(c1 int); insert into t234 values(2); insert into t234 values(3); insert into t234 values(4); select * from t13 union select * from t234 intersect all select * from t12; c1 1 3 2 drop table t12,t13,t234; create table t1 (a int); insert into t1 values (3), (1), (7), (3), (2), (7), (4); create table t2 (a int); insert into t2 values (4), (5), (9), (1), (8), (9), (2), (2); create table t3 (a int); insert into t3 values (8), (1), (8), (2), (3), (7), (2); select * from t1 where a > 4 union all select * from t2 where a < 5 intersect all select * from t3 where a < 5; a 7 7 2 1 2 explain extended select * from t1 where a > 4 union all select * from t2 where a < 5 intersect all select * from t3 where a < 5; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 7 100.00 Using where 4 UNION ALL NULL NULL NULL NULL 7 100.00 2 DERIVED t2 ALL NULL NULL NULL NULL 8 100.00 Using where 3 INTERSECT t3 ALL NULL NULL NULL NULL 7 100.00 Using where NULL INTERSECT RESULT ALL NULL NULL NULL NULL NULL NULL Warnings: Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` > 4 union all /* select#4 */ select `__4`.`a` AS `a` from (/* select#2 */ select `test`.`t2`.`a` AS `a` from `test`.`t2` where `test`.`t2`.`a` < 5 intersect all /* select#3 */ select `test`.`t3`.`a` AS `a` from `test`.`t3` where `test`.`t3`.`a` < 5) `__4` drop table t1,t2,t3;