Sehen Sie sich diesen Artikel auf Simple-talk.com von Pop Rivett an. Es führt Sie durch die Erstellung eines generischen Triggers, der den OLDVALUE und den NEWVALUE für alle aktualisierten Spalten protokolliert. Der Code ist sehr generisch und Sie können ihn auf jede Tabelle anwenden, die Sie prüfen möchten, auch auf jede CRUD-Operation, d. h. INSERT, UPDATE und DELETE. Die einzige Voraussetzung ist, dass Ihre zu auditierende Tabelle einen PRIMARY KEY haben sollte (den die meisten gut entworfenen Tabellen sowieso haben sollten).
Hier ist der relevante Code für Ihren GUESTS-Tisch.
- AUDIT-Tabelle erstellen.
IF NOT EXISTS
(SELECT * FROM sysobjects WHERE id = OBJECT_ID(N'[dbo].[Audit]')
AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
CREATE TABLE Audit
(Type CHAR(1),
TableName VARCHAR(128),
PK VARCHAR(1000),
FieldName VARCHAR(128),
OldValue VARCHAR(1000),
NewValue VARCHAR(1000),
UpdateDate datetime,
UserName VARCHAR(128))
GO
- ERSTELLEN Sie wie folgt einen UPDATE-Trigger für die GUESTS-Tabelle.
CREATE TRIGGER TR_GUESTS_AUDIT ON GUESTS FOR UPDATE
AS
DECLARE @bit INT ,
@field INT ,
@maxfield INT ,
@char INT ,
@fieldname VARCHAR(128) ,
@TableName VARCHAR(128) ,
@PKCols VARCHAR(1000) ,
@sql VARCHAR(2000),
@UpdateDate VARCHAR(21) ,
@UserName VARCHAR(128) ,
@Type CHAR(1) ,
@PKSelect VARCHAR(1000)
--You will need to change @TableName to match the table to be audited.
-- Here we made GUESTS for your example.
SELECT @TableName = 'GUESTS'
-- date and user
SELECT @UserName = SYSTEM_USER ,
@UpdateDate = CONVERT (NVARCHAR(30),GETDATE(),126)
-- Action
IF EXISTS (SELECT * FROM inserted)
IF EXISTS (SELECT * FROM deleted)
SELECT @Type = 'U'
ELSE
SELECT @Type = 'I'
ELSE
SELECT @Type = 'D'
-- get list of columns
SELECT * INTO #ins FROM inserted
SELECT * INTO #del FROM deleted
-- Get primary key columns for full outer join
SELECT @PKCols = COALESCE(@PKCols + ' and', ' on')
+ ' i.' + c.COLUMN_NAME + ' = d.' + c.COLUMN_NAME
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS pk ,
INFORMATION_SCHEMA.KEY_COLUMN_USAGE c
WHERE pk.TABLE_NAME = @TableName
AND CONSTRAINT_TYPE = 'PRIMARY KEY'
AND c.TABLE_NAME = pk.TABLE_NAME
AND c.CONSTRAINT_NAME = pk.CONSTRAINT_NAME
-- Get primary key select for insert
SELECT @PKSelect = COALESCE(@PKSelect+'+','')
+ '''<' + COLUMN_NAME
+ '=''+convert(varchar(100),
coalesce(i.' + COLUMN_NAME +',d.' + COLUMN_NAME + '))+''>'''
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS pk ,
INFORMATION_SCHEMA.KEY_COLUMN_USAGE c
WHERE pk.TABLE_NAME = @TableName
AND CONSTRAINT_TYPE = 'PRIMARY KEY'
AND c.TABLE_NAME = pk.TABLE_NAME
AND c.CONSTRAINT_NAME = pk.CONSTRAINT_NAME
IF @PKCols IS NULL
BEGIN
RAISERROR('no PK on table %s', 16, -1, @TableName)
RETURN
END
SELECT @field = 0,
@maxfield = MAX(ORDINAL_POSITION)
FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = @TableName
WHILE @field < @maxfield
BEGIN
SELECT @field = MIN(ORDINAL_POSITION)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = @TableName
AND ORDINAL_POSITION > @field
SELECT @bit = (@field - 1 )% 8 + 1
SELECT @bit = POWER(2,@bit - 1)
SELECT @char = ((@field - 1) / 8) + 1
IF SUBSTRING(COLUMNS_UPDATED(),@char, 1) & @bit > 0
OR @Type IN ('I','D')
BEGIN
SELECT @fieldname = COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = @TableName
AND ORDINAL_POSITION = @field
SELECT @sql = '
insert Audit ( Type,
TableName,
PK,
FieldName,
OldValue,
NewValue,
UpdateDate,
UserName)
select ''' + @Type + ''','''
+ @TableName + ''',' + @PKSelect
+ ',''' + @fieldname + ''''
+ ',convert(varchar(1000),d.' + @fieldname + ')'
+ ',convert(varchar(1000),i.' + @fieldname + ')'
+ ',''' + @UpdateDate + ''''
+ ',''' + @UserName + ''''
+ ' from #ins i full outer join #del d'
+ @PKCols
+ ' where i.' + @fieldname + ' <> d.' + @fieldname
+ ' or (i.' + @fieldname + ' is null and d.'
+ @fieldname
+ ' is not null)'
+ ' or (i.' + @fieldname + ' is not null and d.'
+ @fieldname
+ ' is null)'
EXEC (@sql)
END
END
GO
