[SQL][Resolved] #1063 - Incorrect column specifier for column 'user_id'

Since auto_increment columns must be integer type (TINYINT, SMALLINT, INTEGER, or BIGINT), I use varchar as type of value with “auto_increment” with cause error

This is my case,

CREATE TABLE  .`p_users` (

 `user_id` VARCHAR( 15 ) AUTO_INCREMENT ,

 `username` VARCHAR( 20 ) NOT NULL ,

 `nickname` VARCHAR( 20 ) NOT NULL ,

 `password` VARCHAR( 20 ) NOT NULL ,

 `permission` VARCHAR( 10 ) NOT NULL ,

 `email` VARCHAR( 50 ) NOT NULL ,

 `reg_time` TIMESTAMP NOT NULL ,

 `reg_code` TEXT NOT NULL ,

 `reset_code` TEXT NOT NULL ,

PRIMARY KEY (  `user_id` )

) ENGINE = MYISAM

 Corrected :

CREATE TABLE  `p_users` (

 `user_id` INTEGER( 15 ) AUTO_INCREMENT,

 `username` VARCHAR( 20 ) NOT NULL ,

 `nickname` VARCHAR( 20 ) NOT NULL ,

 `password` VARCHAR( 20 ) NOT NULL ,

 `permission` VARCHAR( 10 ) NOT NULL ,

 `email` VARCHAR( 50 ) NOT NULL ,

 `reg_time` TIMESTAMP NOT NULL ,

 `reg_code` TEXT NOT NULL ,

 `reset_code` TEXT NOT NULL ,

PRIMARY KEY (  `user_id` )

) ENGINE = MYISAM