# 1班NodeJs笔记

**Repository Path**: li-changbao/class-1---node-js-notes

## Basic Information

- **Project Name**: 1班NodeJs笔记
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 48
- **Created**: 2022-02-21
- **Last Updated**: 2024-06-05

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# 1班NodeJs笔记

## 新春快乐！欢迎回来各位童鞋！

https://blog.csdn.net/weixin_55664293/article/details/123649230

https://blog.csdn.net/njcyp123456789/article/details/54346477

--2
create trigger [TR_0]
on database
for drop_table,alter_table
as
begin 
	raiserror('禁止删除表',11,1)
	rollback
end
drop table SC

--3
drop trigger [TR_0] on database

--4
create trigger [TR-1]
on [dbo].[SC]
after insert,update
as
begin
	declare @count int=0,@cno int
	select @cno=inserted.cno from inserted 
	select @count=count(*) from [dbo].[SC]s  where s.Cno=@cno
	if @count>3
	begin
		raiserror('超过选修人数上限',11,1)
		rollback
	end
end
--5
create trigger [TR-2]
on [dbo].[SC]
after insert,update
as
begin
	declare @score int =0;
	select @score=inserted.Grade from inserted
	if @score>100 or @score<0
	begin
		raiserror('成绩不合法',11,1)
		rollback
	end
end
--6
create trigger [TR-3]
on Student
for  update
as
begin
	if(UPDATE(sno))
	begin
		raiserror('不得修改主键',11,1)
		rollback
	end
end
--7
create trigger [TR-4]
on Student
for  insert
as
begin
	declare @zno int,@son nvarchar(9)
	select @zno=RIGHT(RTRIM(inserted.Sno),1),@son=inserted.Sno  from inserted
	insert fenzhu values(@son,@zno);
end
--8
create trigger [TR-5]
on Student
for  delete
as
begin
	declare @son varchar
	select @son=inserted.Sno  from inserted
	delete fenzhu where sno=@son
end
--9

create trigger [TR-6]
on Course
instead of  update
as
begin
	raiserror('不能修改课程表所有信息',11,1)
	rollback
end