昨天面试时,机试有一题要求写一个触发器,之前没写过,那时只能写出个基本语法,但功能实现有错.今天把它实现了..
题目:T1表
CREATE TABLE [dbo].[t1] (
[pid] [int] IDENTITY (1, 1) NOT NULL ,
[price] [float] NOT NULL
) ON [PRIMARY]
GO
T2 表
CREATE TABLE [dbo].[t2] (
[pid] [int] NOT NULL ,
[pitemid] [int] IDENTITY (1, 1) NOT NULL ,
[qty] [float] NOT NULL ,
[psum] [float] NULL
) ON [PRIMARY]
要求写一触发器,插入或更新T2表QTY字段的值时,同时使得psum=qty*T1.Price
今天写的触发器代码:
Create Trigger tg_sum
On dbo.t2
For Insert,Update
As
Update t2 Set psum=qty*price From t2 Inner Join t1 On t2.pid=t1.pid
初学触发器,质量很差.