MYSQL有自增列的表如何创建

USE school;

CREATE TABLE cdat
(
   localt               CHAR(20) NOT NULL,
   cd                   CHAR(5) NOT NULL,
   snosat               CHAR(2) NOT NULL,
   rnorec               CHAR(3) NOT NULL,
   id                   INT(20) NOT NULL AUTO_INCREMENT, --自增列
   PRIMARY KEY (id)
);

INSERT INTO cdat(localt,cd,snosat,rnorec)
SELECT 'cc','ccc','ccd','sddf' UNION ALL
SELECT 'aaa','aaa','a','b' ;

SELECT LAST_INSERT_ID('');
SELECT * FROM cdat;