利用SQL Server触发器实现表的历史修改痕迹记录

2020-02-02 08:04:12王冬梅

CREATE TABLE product_log(name VARCHAR(50),description VARCHAR(200),unit_cost MONEY,pub_time DATETIME,sqlcomm varchar(10),exectime datetime)
GO

新增的两个字段sqlcomm和exectime分别记录执行命令(insert、update和delete)和执行时间

2.增加触发器

在产品表增加触发器,其目的是为了记录表数据发生改变时记录到product_log中。

针对插入(insert)操作,增加名为tr_product_i的触发器:

CREATE TRIGGER tr_product_i
ON product
AFTER INSERT
AS
if @@rowcount = 0 --为了避免占用资源,当影响行数为0时,结束触发器
 return
insert into product_log (name,description,unit_cost,pub_time,sqlcomm,exectime)
 select name,description,unit_cost,pub_time,'insert',getdate() from inserted
GO

针对更新(update)操作,增加名为tr_product_u的触发器:

CREATE TRIGGER tr_product_u
ON product
AFTER UPDATE
AS
if @@rowcount = 0 --为了避免占用资源,当影响行数为0时,结束触发器
 return
/*更新前*/
insert into product_log (name,description,unit_cost,pub_time,sqlcomm,exectime)
 select name,description,unit_cost,pub_time,'update',getdate() from deleted
/*更新后*/
insert into product_log (name,description,unit_cost,pub_time,sqlcomm,exectime)
 select name,description,unit_cost,pub_time,'update',getdate() from inserted
GO

针对删除(delete)操作,增加名为tr_product_d的触发器:

CREATE TRIGGER tr_product_d
ON product
AFTER DELETE
AS
if @@rowcount = 0 --为了避免占用资源,当影响行数为0时,结束触发器
 return
insert into product_log (name,description,unit_cost,pub_time,sqlcomm,exectime)
 select name,description,unit_cost,pub_time,'delete',getdate() from deleted
GO

3.测试触发器

插入(insert)测试

INSERT INTO product(name,description,unit_cost,pub_time)
 VALUES('逗比','这是一个逗比的测试数据',200.5,'1990-11-18')
GO

SELECT * FROM product
SELECT * FROM product_log
GO

更新(update)测试

UPDATE product SET unit_cost=250.0 WHERE name='逗比'
GO

SELECT * FROM product
SELECT * FROM product_log
GO

删除(delete)测试

DELETE FROM product WHERE name='逗比'
GO

SELECT * FROM product
SELECT * FROM product_log
GO

好了这篇文章就介绍到这了,需要的朋友可以参考一下。

相关文章 大家在看