1 --create table users--创建用户表 2 --( 3 -- ids int primary key identity(1,1), 4 -- name nvarchar(200),--姓名 5 -- class nvarchar(200)--班级编号 6 --) 7 8 --create table class--创建班级表 9 --( 10 -- classCode nvarchar(200) primary key,--班级编号 11 -- className nvarchar(200),--班级名字 12 --) 13 14 ----插入班级表数据 15 --insert into class values(‘c001‘,‘一班‘); 16 --insert into class values(‘c002‘,‘二班‘); 17 --insert into class values(‘c003‘,‘三班‘); 18 --insert into class values(‘c004‘,‘四班‘); 19 --insert into class values(‘c005‘,‘五班‘); 20 ----插入用户表数据 21 --insert into users values(‘张一‘,‘c001‘); 22 --insert into users values(‘张二‘,‘c002‘); 23 --insert into users values(‘张三‘,‘c003‘); 24 --insert into users values(‘张四‘,‘c004‘); 25 --insert into users values(‘张五‘,‘c005‘); 26 27 --select * from users; 28 --select * from class; 29 30 ----触发器 31 ----（一个特殊的存储过程，没办法直接调用它，而是通过增删改的动作来触发它 32 ----一个表的一个动作只能有一个触发器） 33 create trigger users_Delete 34 on users 35 for delete--执行delete操作触发，然后执行以下操作 36 as 37 select * from users 38 39 40 create trigger users_Insert 41 on users 42 for insert--执行insert操作触发，然后执行一下操作 43 as 44 select * from users 45 46 create trigger users_Delete 47 on users 48 instead of delete--执行delete操作时，不执行次操作，并用以下操作代替 49 as 50 select * from users 51 52 create trigger users_Delete 53 on users 54 instead of delete 55 as 56 select * from deleted--查询删除的数据 57 58 59 create trigger users_Delete 60 on users 61 instead of delete 62 as 63 declare @a nvarchar(100) 64 select @a=ids from deleted 65 if @a=2 66 begin 67 select ‘太丑了，不能删！‘ 68 end 69 else 70 begin 71 delete from users where ids=@a 72 end 73 74 delete from users where ids=2 75 76 77 78 ----级联删除 79 create trigger class_delete 80 on class 81 instead of delete 82 as 83 declare @a nvarchar(200); 84 select @a=classCode from deleted; 85 delete from users where class=@a; 86 delete from class where classCode=@a; 87 88 delete from class where classcode=‘c001‘;