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create table bool_test(
id INT AUTO_INCREMENT PRIMARY KEY,
bool_val TINYINT UNSIGNED CHECK(bool_val <= 1)
);
insert into bool_test(bool_val) values (0);
insert into bool_test(bool_val) values (1);
insert into bool_test(bool_val) values (null);
insert into bool_test(bool_val) values (2);
Check constraint 'bool_test_chk_1' is violated.
insert into bool_test(bool_val) values (-1);
Out of range value for column 'bool_val' at row 1
select * from bool_test
| id | bool_val |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | null |