These types are synonyms for TINYINT(1).
A value of zero is considered false.
Non-zero values are considered true:
The constants TRUE and FALSE evaluate to 1 and 0, respectively.
mysql> mysql> SELECT TRUE, true, FALSE, false; +------+------+-------+-------+ | TRUE | TRUE | FALSE | FALSE | +------+------+-------+-------+ | 1 | 1 | 0 | 0 | +------+------+-------+-------+ 1 row in set (0.00 sec) mysql>