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create table t1(id int, a int);
insert into t1 values(1,1),(2,2),(3,null);
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
explain select id, a=1 is false from t1 ;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 3 100.00 NULL
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`id` AS `id`,((`test`.`t1`.`a` = 1) is false) AS `a=1 is false` from `test`.`t1`
select id, a=1 is false from t1 ;
id a=1 is false
1 0
2 1
3 0
explain select id, not (a=1 is true) from t1 ;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 3 100.00 NULL
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`id` AS `id`,((`test`.`t1`.`a` = 1) is not true) AS `not (a=1 is true)` from `test`.`t1`
select id, not (a=1 is true) from t1 ;
id not (a=1 is true)
1 0
2 1
3 1
explain select id, (not a=1) is true from t1 ;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 3 100.00 NULL
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`id` AS `id`,((`test`.`t1`.`a` <> 1) is true) AS `(not a=1) is true` from `test`.`t1`
select id, (not a=1) is true from t1 ;
id (not a=1) is true
1 0
2 1
3 0
explain select id, not (a=1 is false) from t1 ;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 3 100.00 NULL
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`id` AS `id`,((`test`.`t1`.`a` = 1) is not false) AS `not (a=1 is false)` from `test`.`t1`
select id, not (a=1 is false) from t1 ;
id not (a=1 is false)
1 1
2 0
3 1
explain select id, not (a=1 is unknown) from t1 ;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 3 100.00 NULL
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`id` AS `id`,((`test`.`t1`.`a` = 1) is not null) AS `not (a=1 is unknown)` from `test`.`t1`
select id, not (a=1 is unknown) from t1 ;
id not (a=1 is unknown)
1 1
2 1
3 0
explain select id, ((not a=1) is true) is false from t1 ;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 3 100.00 NULL
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`id` AS `id`,((`test`.`t1`.`a` <> 1) is not true) AS `((not a=1) is true) is false` from `test`.`t1`
select id, ((not a=1) is true) is false from t1 ;
id ((not a=1) is true) is false
1 1
2 0
3 1
explain select id, 3 + (not (a=1 is false)) from t1 ;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 3 100.00 NULL
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`id` AS `id`,(3 + ((`test`.`t1`.`a` = 1) is not false)) AS `3 + (not (a=1 is false))` from `test`.`t1`
select id, 3 + (not (a=1 is false)) from t1 ;
id 3 + (not (a=1 is false))
1 4
2 3
3 4
drop table t1;
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