数据库量表之间的级联例子

CREATE TABLE mail_model(
id VARCHAR(50) PRIMARY KEY NOT NULL ,
mail_filename VARCHAR(200),
content VARCHAR(2000)
)ENGINE=INNODB DEFAULT CHARSET=gbk;

CREATE TABLE mail_model_extend(
id INT(6) AUTO_INCREMENT NOT NULL PRIMARY KEY,
rid VARCHAR(50) NOT NULL,
content VARCHAR(2000),
INDEX (RID),
FOREIGN KEY (RID) REFERENCES mail_model(ID) ON DELETE CASCADE ON UPDATE CASCADE
)ENGINE=INNODB DEFAULT CHARSET=gbk;

INSERT INTO mail_model(id,mail_filename,content) VALUES('bbb','aaa','aaaa');

INSERT INTO mail_model_extend(rid,content) VALUES('bbb','aaa');

SELECT *FROM mail_model_extend;

SELECT *FROM mail_model;