create trigger deltrigger on employee for
delete
as
if @@rowcount=0
return
if @@rowcount>1
begin
rollback transaction
raiserror('you can only delete one information at one time',16,1)
end
return

楼主是英文不过关吗?
raiseerror连错误描述都给出来了 还问是实现什么功能...

这个trigger实现的功能就是 一次操作只允许删除一条记录 如果超过一条 就拒绝并报错

create trigger deltrigger on employee for
delete
as
if @@rowcount=0
return
if @@rowcount>1
begin
rollback transaction
raiserror('you can only delete one information at one time',16,1)
end
return

这个是比较好的触发器写法(英文书上说),楼主去查一下@@rowcount的帮助就能看懂了.不会的就去查帮助,帮助的解释比较清楚

raiserror 拼写是对的，我删除三条记录，他也能成功

对啊,删除三条当然能成功啦,
if @@rowcount=0
return
这一句才是这个触发器的优秀所在

什么时候会弹出raiserror('you can only delete one information at one time',16,1)的提示信息，if @@rowcount=0
return不理解，
if @@rowcount>1
begin
rollback transaction
raiserror('you can only delete one information at one time',16,1)
end
是说删除的行数大于一行的话就执行begin----end 中的语句麻？还是另有意思？

删除的数多于一条的话就不能让它删除.删除数多于一条就会有警告,这个触发器就是控制只能删除一条的
if @@rowcount=0
return
没有记录被删除就退出触发器.避免它在触发器中逗留的时间过长

我一次删除三条它都不告警呀！

drop trigger deltrigger
go
create trigger deltrigger on tb after
delete
as
if @@rowcount=0
return
if ( select count(*) from deleted )>1
begin
rollback transaction
raiserror('you can only delete one information at one time',16,1)
end
改成这个吧,不知道你那个为什么不行


create trigger deltrigger on tb after
delete
as
declare @count int
set @count=@@rowcount
if @@rowcount=0
return
if @count>1
begin
rollback transaction
raiserror('you can only delete one information at one time',16,1)
end

这样也行.可能是@@rowcount的使用有限制吧,具体的我也不清楚

drop trigger upord
go
create trigger upord on orders
after update
as
declare @row int
set @row = @@rowcount
if @row = 0
return
if (update(p_name))
begin
if @row > 1
begin
rollback transaction
raiserror('you can only one information at one time',16,1)
end
return
update p set p.p_name = i.p_name from product p,inserted i,deleted d where p.p_name = d.p_name
end

我想要实现修改orders的p_name时，product的p_name也更新了，我这样写问题在那里？