Sql Server数据库笔记

1：增加外键

drop table TeacherUser

create table TeacherUser
(
    Id int identity(1,1) primary key not null,
Name nvarchar not null,
studentID int not null
foreign key (studentID) references testDB.[dbo].[StudentUser](id)
)


alter table testDB.[dbo].TeacherUser

add constraint keyword foreign  key(studentID) references testDB.[dbo].[StudentUser](id)

--更新门票触发器
create trigger tgr_update_admissionstatus
on [dbo].[AdmissionTicketProduct] for update
as
  if(update(Status))
  begin
   declare @status int;
   declare @productId int;
   select @status=inserted.status,@productId=inserted.ID from inserted
   if(@status=2)
     update [dbo].[SpecialProduct] set status=1 where ProductId=@productId and ProductType=16
else
update [dbo].[SpecialProduct] set status=2 where ProductId=@productId and ProductType=16
  end
 go


--创建线路触发器
create trigger tgr_update_linestatus
on [dbo].TourProduct for update
as
  if(update(Status))
  begin
   declare @status int;
   declare @productId int;
   select @status=inserted.status,@productId=inserted.ID from inserted
   if(@status=64)
     update [dbo].[SpecialProduct] set status=1 where ProductId=@productId and (ProductType=1 or ProductType=2)
else
update [dbo].[SpecialProduct] set status=2 where ProductId=@productId and (ProductType=1 or ProductType=2)
  end
 go


 --创建酒店触发器
 create trigger tgr_update_Hotelstatus
on [dbo].HotelProduct for update
as
  if(update(Status))
  begin
   declare @status int;
   declare @productId int;
   select @status=inserted.status,@productId=inserted.ID from inserted
   if(@status=2)
     update [dbo].[SpecialProduct] set status=1 where ProductId=@productId and ProductType=4
else
update [dbo].[SpecialProduct] set status=2 where ProductId=@productId and ProductType=4
  end
 go


 --创建机票触发器
create trigger tgr_update_flightstatus
on [dbo].AirTicket for update
as
  if(update(Status))
  begin
   declare @status int;
   declare @productId int;
   select @status=inserted.status,@productId=inserted.ID from inserted
   if(@status=2)
     update [dbo].[SpecialProduct] set status=1 where ProductId=@productId and ProductType=8
else
update [dbo].[SpecialProduct] set status=2 where ProductId=@productId and ProductType=8
  end
 go