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  • 数据库触发器

    create trigger user_Delete//创建一个名为user_Delete的触发器
                    on User  //针对于User表
                    for Delete   //执行删除操作
                    as //执行完后要干的事情
                    Select* from User  //查询user表
    
    
    
                   create trigger user_Delete//创建一个名为user_Delete的触发器
                    on User  //针对于User表
                   //如果执行的是Delete事件将会被Select * from deleted 语句代替
                    instead of Delete
                    as
                    Select* from deleted  //(查看你要删除的数据)
    
    
    
                   create trigger user_Delete//创建一个名为user_Delete的触发器
                    on User  //针对于User表
                    instead of Delete
                    as
                    declare @a nvarchar(200);//声明一个字符串类型的a的变量
                    Select @a = ids from deleted;//获取要删除的数据的ids列并赋值给a
                if @a = 5;//如果a=5
                begin
                    select '不能删除'
                    end//不等于5
                    else
                begin
                delete  from users where ids=@a
                    end
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  • 原文地址:https://www.cnblogs.com/skyhorseyk/p/9098740.html
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