我有两张表Customers和AuditTable。当我修改Customers表时，我需要在AuditTable中插入一条新记录：
CREATE TABLE [dbo].[AuditTable]
(
[Id] [int] IDENTITY(1,1) NOT NULL,
[StateBefore] [nvarchar](max) NULL,
[StateAfter] [nvarchar](max) NULL
)
我需要在更新之前和之后将Customer状态的XML表示放入StateBefore和StateAfter。
Customer表是：
CREATE TABLE [dbo].[Customer]
(
[Id] [int] IDENTITY(1,1) NOT NULL,
[Name] [nvarchar](256) NOT NULL,
[Email] [nvarchar](max) NOT NULL,
[IsDeleted] [bit] NULL,
[CreatedUtc] [datetime] NOT NULL,
[UpdatedUtc] [datetime] NULL,
[Version] [timestamp] NOT NULL,
CONSTRAINT [PK_dbo.Customer]
PRIMARY KEY CLUSTERED ([Id] ASC)
WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF,
IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON,
ALLOW_PAGE_LOCKS = ON)
)
GO
ALTER TABLE [dbo].[Customer]
ADD DEFAULT (getutcdate()) FOR [CreatedUtc]
GO
我找到了如何获取行的xml表示的方法：
SELECT
[State] = (SELECT *
FROM dbo.Customer [Customer]
WHERE [Customer].Id = cust.Id
FOR XML AUTO
)
FROM
dbo.Customer cust
仅举例来说。所以在我的触发器中，我需要创建来自deleted和inserted表的行的xml表示。
这是触发器：
ALTER TRIGGER [dbo].[UpdateCustomerTrigger]
ON [dbo].[Customer]
FOR UPDATE
AS
BEGIN
UPDATE Customer
SET UpdatedUtc = GETDATE()
FROM INSERTED
WHERE inserted.id = Customer.Id
-- here I need to insert new records into AuditTable
END
那么，我如何加入deleted和inserted表的两个表示来正确地将它们插入AuditTable？感谢。
答案 0 :(得分：4)
很高兴你已经找到了解决方案......
我只是在想类似的事情......
在任何微小变化时，您的方法都会完整记录的两个副本。因为我必须处理有很多列的表，其中一些是BLOB，这不适合我。
好吧，我没有找到一个绝对“干净”的方法，但是通过以下内容，您将获得一个AuditLog，其中仅包含已更改为更好阅读风格的值。
也许你喜欢它：
INSERT和DELETE及NULL值的支持。尝试一下：
CREATE TABLE AuditTest(TableSchema VARCHAR(250), TableName VARCHAR(250), AuditType VARCHAR(250),Content XML, LogDate DATETIME DEFAULT GETDATE());
GO
CREATE TABLE dbo.Test(ID INT,Test1 VARCHAR(100),Test2 DATETIME,ModifyCounter INT DEFAULT 0,LastModified DATETIME DEFAULT GETDATE());
INSERT INTO dbo.Test(ID,Test1,Test2) VALUES
(1,'Test1',{d'2001-01-01'})
,(2,'Test2',{d'2002-02-02'});
- 当前内容
SELECT * FROM dbo.Test;
GO
- 审核的触发器
CREATE TRIGGER [dbo].[UpdateTestTrigger]
ON [dbo].[Test]
FOR UPDATE,INSERT,DELETE
AS
BEGIN
IF NOT EXISTS(SELECT 1 FROM deleted) AND NOT EXISTS(SELECT 1 FROM inserted) RETURN;
DECLARE @tp VARCHAR(10)=CASE WHEN EXISTS(SELECT 1 FROM deleted) AND EXISTS(SELECT 1 FROM inserted) THEN 'upd'
ELSE CASE WHEN EXISTS(SELECT 1 FROM deleted) AND NOT EXISTS(SELECT 1 FROM inserted) THEN 'del' ELSE 'ins' END END;
WITH UpdateableCTE AS
(
SELECT t.LastModified,t.ModifyCounter
FROM dbo.Test AS t
INNER JOIN inserted AS i ON t.ID=i.ID
)
UPDATE UpdateableCTE SET LastModified=GETDATE()
,ModifyCounter=ModifyCounter+1;
SELECT * INTO #tmpInserted FROM inserted;
SELECT * INTO #tmpDeleted FROM deleted;
DECLARE @tableSchema VARCHAR(250)='dbo';
DECLARE @tableName VARCHAR(250)='Test';
DECLARE @cols VARCHAR(MAX)=
STUFF
(
(
SELECT ',' + CASE WHEN @tp='upd' THEN
'CASE WHEN (i.[' + COLUMN_NAME + ']!=d.[' + COLUMN_NAME + '] ' +
'OR (i.[' + COLUMN_NAME + '] IS NULL AND d.[' + COLUMN_NAME + '] IS NOT NULL) ' +
'OR (i.['+ COLUMN_NAME + '] IS NOT NULL AND d.[' + COLUMN_NAME + '] IS NULL)) ' +
'THEN ' ELSE '' END +
'(SELECT ''' + COLUMN_NAME + ''' AS [@name]' +
CASE WHEN @tp IN ('upd','del') THEN ',ISNULL(CAST(d.[' + COLUMN_NAME + '] AS NVARCHAR(MAX)),N''##NULL##'') AS [@old]' ELSE '' END +
CASE WHEN @tp IN ('ins','upd') THEN ',ISNULL(CAST(i.[' + COLUMN_NAME + '] AS NVARCHAR(MAX)),N''##NULL##'') AS [@new] ' ELSE '' END +
' FOR XML PATH(''Column''),TYPE) ' + CASE WHEN @tp='upd' THEN 'END' ELSE '' END
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA=@tableSchema AND TABLE_NAME=@tableName
FOR XML PATH('')
),1,1,''
);
DECLARE @cmd VARCHAR(MAX)=
'SET LANGUAGE ENGLISH;
WITH ChangedColumns AS
(
SELECT COALESCE(i.ID,d.ID) AS ID
,Col.*
FROM #tmpInserted AS i
FULL OUTER JOIN #tmpDeleted AS d ON i.ID=d.ID
CROSS APPLY
(
SELECT ' + @cols + '
FOR XML PATH(''''),TYPE
) AS Col([Column])
)
INSERT INTO AuditTest(TableSchema,TableName,AuditType,Content)
SELECT ''' + @tableSchema + ''',''' + @tableName + ''',''' + @tp + '''
,(
SELECT ''' + @tableSchema + ''' AS [@TableSchema]
,''' + @tableName + ''' AS [@TableName]
,''' + @tp + ''' AS [@ActionType]
,(
SELECT ChangedColumns.ID AS [@ID]
,(
SELECT x.[Column] AS [*],''''
FROM ChangedColumns AS x WHERE x.ID=ChangedColumns.ID
FOR XML PATH(''''),TYPE
)
FROM ChangedColumns
FOR XML PATH(''Row''),TYPE
)
FOR XML PATH(''Changes'')
);';
EXEC (@cmd);
DROP TABLE #tmpInserted;
DROP TABLE #tmpDeleted;
END
GO
- 现在让我们用一些操作来测试它：
UPDATE dbo.Test SET Test1='New 1' WHERE ID=1;
UPDATE dbo.Test SET Test1='New 1',Test2={d'2000-01-01'} ;
DELETE FROM dbo.Test WHERE ID=2;
DELETE FROM dbo.Test WHERE ID=99; --no affect
INSERT INTO dbo.Test(ID,Test1,Test2) VALUES
(3,'Test3',{d'2001-03-03'})
,(4,'Test4',{d'2001-04-04'})
,(5,'Test5',{d'2001-05-05'});
UPDATE dbo.Test SET Test2=NULL; --all rows
DELETE FROM dbo.Test WHERE ID IN (1,3);
GO
- 检查最终状态
SELECT * FROM dbo.Test;
SELECT * FROM AuditTest;
GO
- 清理
DROP TABLE dbo.Test;
GO
DROP TABLE dbo.AuditTest;
GO
<Changes TableSchema="dbo" TableName="Test" ActionType="upd">
<Row ID="2">
<Column name="Test1" old="Test2" new="New 1" />
<Column name="Test2" old="Feb 2 2002 12:00AM" new="Jan 1 2000 12:00AM" />
</Row>
<Row ID="1">
<Column name="Test2" old="Jan 1 2001 12:00AM" new="Jan 1 2000 12:00AM" />
</Row>
</Changes>
INSERT操作的结果：三个新行<Changes TableSchema="dbo" TableName="Test" ActionType="ins">
<Row ID="5">
<Column name="ID" new="5" />
<Column name="Test1" new="Test5" />
<Column name="Test2" new="May 5 2001 12:00AM" />
<Column name="ModifyCounter" new="0" />
<Column name="LastModified" new="Aug 18 2017 5:48PM" />
</Row>
<Row ID="4">
<Column name="ID" new="4" />
<Column name="Test1" new="Test4" />
<Column name="Test2" new="Apr 4 2001 12:00AM" />
<Column name="ModifyCounter" new="0" />
<Column name="LastModified" new="Aug 18 2017 5:48PM" />
</Row>
<Row ID="3">
<Column name="ID" new="3" />
<Column name="Test1" new="Test3" />
<Column name="Test2" new="Mar 3 2001 12:00AM" />
<Column name="ModifyCounter" new="0" />
<Column name="LastModified" new="Aug 18 2017 5:48PM" />
</Row>
</Changes>
DELETE操作的结果<Changes TableSchema="dbo" TableName="Test" ActionType="del">
<Row ID="3">
<Column name="ID" old="3" />
<Column name="Test1" old="Test3" />
<Column name="Test2" old="##NULL##" />
<Column name="ModifyCounter" old="2" />
<Column name="LastModified" old="Aug 18 2017 5:48PM" />
</Row>
<Row ID="1">
<Column name="ID" old="1" />
<Column name="Test1" old="New 1" />
<Column name="Test2" old="##NULL##" />
<Column name="ModifyCounter" old="3" />
<Column name="LastModified" old="Aug 18 2017 5:48PM" />
</Row>
</Changes>
答案 1 :(得分：2)
我找到了解决方案。这是触发器代码：
USE [ISContext]
GO
/****** Object: Trigger [dbo].[UpdateCustomerTrigger] Script Date: 22.05.2016 10:40:39 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER TRIGGER [dbo].[UpdateCustomerTrigger]
ON [dbo].[Customer]
FOR UPDATE
AS
BEGIN
UPDATE Customer SET UpdatedUtc = GETDATE()
FROM INSERTED
WHERE inserted.id=Customer.Id
INSERT INTO [dbo].[AuditTable]
SELECT
StateBefore =
(
SELECT *
FROM deleted [Customer]
WHERE [Customer].Id = cust.Id
FOR XML AUTO
),
[StateAfter] =(
SELECT *
FROM inserted [Customer]
WHERE [Customer].Id = cust.Id
FOR XML AUTO
)
FROM inserted cust
END