Tracking changes to database rows (SQL Server)

Question

Possible Duplicate:
Auditing SQL Server data changes

My requirements demand for each row inserted and updated in the database to track who made the change (creator/modifier), when the record was created and when it was modified. I have guids for row IDs in all tables, so I thought I would come up with a table rowdata

rowdata: created (datetime), modified (datetime), createdby (string or user id), modifiedby and maybe summary column (string, summary of changes)

and then put some insert/update triggers in place. Do you think is fine or is there another wa (maybe out-of-the-box one)?

My dev environment is .NET 4, so if you think of other options that might come into question, please tell.

Answer 1

I have similar requirements but went about it by adding these four columns to all the tables that needed the auditing tracked:

[Create_User] [nvarchar](100) NULL,
[Create_Date] [datetimeoffset](7) NULL,
[Modify_User] [nvarchar](100) NULL,
[Modify_Date] [datetimeoffset](7) NULL,

The INSERT trigger looks like:

CREATE TRIGGER [SomeSchema].[Some_Table_Insert_Create] ON [SomeSchema].[Some_Table] FOR INSERT AS 
   SET NOCOUNT ON

   IF EXISTS(SELECT * FROM INSERTED WHERE Create_User IS NOT NULL)
      BEGIN   
         UPDATE [SomeSchema].[Some_Table] SET 
            Create_Date = SYSDATETIMEOFFSET()
         FROM 
            [SomeSchema].[Some_Table]
         INNER JOIN 
            INSERTED 
         ON 
            [SomeSchema].[Some_Table].Some_Table_Id = INSERTED.Some_Table_Id
      END
   ELSE
      BEGIN
         UPDATE [SomeSchema].[Some_Table] SET 
            Create_User = SUSER_SNAME(),
            Create_Date = SYSDATETIMEOFFSET()
         FROM 
            [SomeSchema].[Some_Table]
         INNER JOIN 
            INSERTED 
         ON 
            [SomeSchema].[Some_Table].Some_Table_Id = INSERTED.Some_Table_Id
      END

And the UPDATE trigger looks like:

CREATE TRIGGER [SomeSchema].[Some_Table_Update_Modify] ON [SomeSchema].[Some_Table] FOR UPDATE AS 

   SET NOCOUNT ON

   IF NOT UPDATE (Create_User) AND NOT UPDATE (Create_Date)
      BEGIN
         IF EXISTS(SELECT * FROM INSERTED WHERE Modify_User IS NOT NULL)
             BEGIN  
                 UPDATE [SomeSchema].[Some_Table] SET 
                     Modify_Date = SYSDATETIMEOFFSET()
                 FROM 
                     [SomeSchema].[Some_Table]
                 INNER JOIN 
                     INSERTED 
                 ON 
                     [SomeSchema].[Some_Table].Some_Table_Id = INSERTED.Some_Table_Id
             END
         ELSE
             BEGIN
                 UPDATE [SomeSchema].[Some_Table] SET 
                     Modify_User = SUSER_SNAME(),
                     Modify_Date = SYSDATETIMEOFFSET() 
                 FROM 
                     [SomeSchema].[Some_Table]
                 INNER JOIN 
                     INSERTED 
                 ON 
                     [SomeSchema].[Some_Table].Some_Table_Id = INSERTED.Some_Table_Id
             END
      END

The SUSER_SNAME() function is useful for use because we are using impersonation in our app and windows authentication to connect to the DB. This may not work in your case.

Answer 2

Triggers are indeed the number one option for auditing tables in this way.