[英]SQL Server trigger to check if column value was changed to insert
我大约有25个表,每个表都有3个触发器(插入,更新,删除)以生成有关用户操作的日志。 每次在UI中进行编辑时,所有这些表都会更新,尽管它们的值不会在UI中更改。
在这种情况下,我不能只检查是否更新了列,还需要检查以前的更新值是否与新更新的值不同,以便可以将其插入到日志表中。 另外,我需要将所有更新的表值插入到日志表中,以逗号分隔的字符串形式。
有什么有效的方法来解决这个问题吗?
ALTER TRIGGER [dbo].[Activity_Update]
ON [dbo].[Activity]
AFTER UPDATE
AS
BEGIN
DECLARE @Names VARCHAR(8000)
SET @result = ' '
DECLARE @id INT;
SELECT @id = i.ID FROM inserted i;
IF UPDATE(deptNotes)
BEGIN
DECLARE @OldValue NVARCHAR(MAX)
SELECT TOP 1 @OldValue = deptNotes
FROM Activity
WHERE id = @id
ORDER BY Timestamp DESC
IF (@OldValue != (SELECT i.deptNotes FROM inserted i))
BEGIN
IF ((SELECT i.deptNotes FROM inserted i) != ' ')
SELECT @result = @result + ',' + 'Modified dept. Notes'
ELSE
SELECT @result = @result + ',' + 'Removed dept. Notes'
END
END
IF UPDATE(deptActivityID)
BEGIN
DECLARE @OldValue1 NVARCHAR(MAX)
SELECT TOP 1 @OldValue1 = deptActivityID
FROM Activity
WHERE id = @id
ORDER BY Timestamp DESC
IF (@OldValue1 != (SELECT i.deptActivityID FROM inserted i))
BEGIN
SELECT @result = @result + ',' + 'Changed dept. Activity '
END
END
IF UPDATE(SubmissionDate)
BEGIN
declare @OldValue2 nvarchar(max)
select Top 1 @OldValue2 = submissiondate from [Activity] where id=@id Order by Timestamp DESC
If (@OldValue2 != (select i.submissiondate from inserted i))
BEGIN
Select @result = @result + ',' + 'Changed application date - ' + '"' + (select cast(i.submissiondate as nvarchar(500)) from inserted i)+ '"'
END
END
INSERT [Activity]
(
[deptActivityID],
[deptNotes],
[SubmissionDate],
[Username],
[Operation],
[Comment]
)
SELECT
v.deptActivityID,
v.deptNotes,
v.SubmissionDate,
v.[LastEditBy],
'update',
@result
FROM inserted v
END
GO
您可以使用deleted
表找出旧值,然后inserted
新值。 另请注意,INSERT,UPDATE和DELETE可能影响多个行,因此您应由触发器处理。
下面的触发代码将为您提供deptNotes中任何更改的行列表。
select 'deptActivityID ' + d.deptActivityID +
' Changed from ' + d.deptNotes + ' to ' + i.deptNotes
from deleted d
inner join inserted i on d.deptActivityID = i.deptActivityID
where d.deptNotes <> i.deptNotes
如果您的deptNotes可能包含NULL值,则需要使用ISNULL()来处理
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.