Create a table by test
CREATE TABLE `table` (
`sex` ENUM('Y','N') NOT NULL COMMENT 'my comment'
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB;
Now, let's add a default value.
ALTER TABLE `table`
CHANGE COLUMN `sex` `sex` ENUM('Y','N') NOT NULL DEFAULT 'Y' COMMENT 'my comment' FIRST;
You can't see COMMENT. but I can see it by mysql commmand.
mysql> show create table `table`