外键表
ondeletecascade
ondeletecascade关系表的级联更新: on update cascadeon delete cascade 是级联删除的意思意思是当你更新或删除主键表时,那么外键表也会跟随⼀起更新或删除CREATE TABLE Countries(CountryId INT PRIMARY KEY)INSERT INTO Countries (CountryId) VALUES (1)INSERT I...
ondeletecascade关系表的级联更新: on update cascadeon delete cascade 是级联删除的意思意思是当你更新或删除主键表时,那么外键表也会跟随⼀起更新或删除CREATE TABLE Countries(CountryId INT PRIMARY KEY)INSERT INTO Countries (CountryId) VALUES (1)INSERT I...