mysql basic

CREATE TABLE

 CREATE TABLE `critical_url` (
  `id`               INTEGER AUTO_INCREMENT NOT NULL PRIMARY KEY,
  `logical_name`     VARCHAR(100)           NOT NULL,
  `subtype`          VARCHAR(20)            NOT NULL
);

### CHANGE COLUMN NAME ``` ALTER TABLE `critical_urltest` CHANGE `gender` `sex` VARCHAR(10) NOT NULL;

### ADD COLUMN

ALTER TABLE critical_urltest
ADD COLUMN last_name VARCHAR(20) DEFAULT "zhou" NOT NULL;

OR

ALTER TABLE critical_urltest
ADD COLUMN last_name VARCHAR(20) NOT NULL;