create table t1 (a int, b int);
create table t2 (c int, d int);
insert into t1 values (1,1),(2,2);
insert into t2 values (2,2),(3,3);
(select a,b from t1) except (select c,d from t2);
a	b
1	1
EXPLAIN (select a,b from t1) except (select c,d from t2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
2	EXCEPT	t2	ALL	NULL	NULL	NULL	NULL	2	
NULL	UNION RESULT	<union1,2>	ALL	NULL	NULL	NULL	NULL	NULL	
EXPLAIN extended (select a,b from t1) except (select c,d from t2);
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	
2	EXCEPT	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	
NULL	UNION RESULT	<union1,2>	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`) except (/* select#2 */ select `test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2`)
EXPLAIN extended select * from ((select a,b from t1) except (select c,d from t2)) a;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	<derived2>	ALL	NULL	NULL	NULL	NULL	2	100.00	
2	DERIVED	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	
3	EXCEPT	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	
NULL	UNION RESULT	<union2,3>	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`) except (/* select#3 */ select `test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2`)) `a`
EXPLAIN format=json (select a,b from t1) except (select c,d from t2);
EXPLAIN
{
  "query_block": {
    "union_result": {
      "table_name": "<union1,2>",
      "access_type": "ALL",
      "query_specifications": [
        {
          "query_block": {
            "select_id": 1,
            "table": {
              "table_name": "t1",
              "access_type": "ALL",
              "rows": 2,
              "filtered": 100
            }
          }
        },
        {
          "query_block": {
            "select_id": 2,
            "operation": "EXCEPT",
            "table": {
              "table_name": "t2",
              "access_type": "ALL",
              "rows": 2,
              "filtered": 100
            }
          }
        }
      ]
    }
  }
}
ANALYZE format=json (select a,b from t1) except (select c,d from t2);
ANALYZE
{
  "query_block": {
    "union_result": {
      "table_name": "<union1,2>",
      "access_type": "ALL",
      "r_loops": 1,
      "r_rows": 1,
      "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": 2,
              "r_rows": 2,
              "r_total_time_ms": "REPLACED",
              "filtered": 100,
              "r_filtered": 100
            }
          }
        },
        {
          "query_block": {
            "select_id": 2,
            "operation": "EXCEPT",
            "r_loops": 1,
            "r_total_time_ms": "REPLACED",
            "table": {
              "table_name": "t2",
              "access_type": "ALL",
              "r_loops": 1,
              "rows": 2,
              "r_rows": 2,
              "r_total_time_ms": "REPLACED",
              "filtered": 100,
              "r_filtered": 100
            }
          }
        }
      ]
    }
  }
}
ANALYZE format=json select * from ((select a,b from t1) except (select c,d from t2)) a;
ANALYZE
{
  "query_block": {
    "select_id": 1,
    "r_loops": 1,
    "r_total_time_ms": "REPLACED",
    "table": {
      "table_name": "<derived2>",
      "access_type": "ALL",
      "r_loops": 1,
      "rows": 2,
      "r_rows": 1,
      "r_total_time_ms": "REPLACED",
      "filtered": 100,
      "r_filtered": 100,
      "materialized": {
        "query_block": {
          "union_result": {
            "table_name": "<union2,3>",
            "access_type": "ALL",
            "r_loops": 1,
            "r_rows": 1,
            "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": 2,
                    "r_rows": 2,
                    "r_total_time_ms": "REPLACED",
                    "filtered": 100,
                    "r_filtered": 100
                  }
                }
              },
              {
                "query_block": {
                  "select_id": 3,
                  "operation": "EXCEPT",
                  "r_loops": 1,
                  "r_total_time_ms": "REPLACED",
                  "table": {
                    "table_name": "t2",
                    "access_type": "ALL",
                    "r_loops": 1,
                    "rows": 2,
                    "r_rows": 2,
                    "r_total_time_ms": "REPLACED",
                    "filtered": 100,
                    "r_filtered": 100
                  }
                }
              }
            ]
          }
        }
      }
    }
  }
}
select * from ((select a,b from t1) except (select c,d from t2)) a;
a	b
1	1
prepare stmt from "(select a,b from t1) except (select c,d from t2)";
execute stmt;
a	b
1	1
execute stmt;
a	b
1	1
prepare stmt from "select * from ((select a,b from t1) except (select c,d from t2)) a";
execute stmt;
a	b
1	1
execute stmt;
a	b
1	1
drop tables t1,t2;
select 1 as a from dual except select 1 from dual;
a
(select 1 from dual) except (select 1 from dual);
1
(select 1 from dual into @v) except (select 1 from dual);
ERROR HY000: Incorrect usage of EXCEPT and INTO
select 1 from dual ORDER BY 1 except 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 'except select 1 from dual' at line 1
select 1 as a from dual union all select 1 from dual;
a
1
1
select 1 from dual except all select 1 from dual;
ERROR HY000: Incorrect usage of EXCEPT and ALL
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");
insert into t2 values (2, "fgh", 2, "dffggtt"),(3, "ffggddd", 3, "dfgg");
(select a,b,b1 from t1) except (select c,d,d1 from t2);
a	b	b1
1	ddd	sdfrrwwww
create table t3 (select a,b,b1 from t1) except (select c,d,d1 from t2);
show create table t3;
Table	Create Table
t3	CREATE TABLE `t3` (
  `a` int(11) DEFAULT NULL,
  `b` blob DEFAULT NULL,
  `b1` blob DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop tables t1,t2,t3;