Timestamp problem

toddb1389 posted on Thursday, May 24, 2007

I'm working on my first CSLA app and I'm getting a "Row edited by another user" error when I update an object.  The relevant code is:

In DataPortal_Update:
cm.Parameters.Add("@lastChanged", SqlDbType.Timestamp);
cm.Parameters["@lastChanged"].Value = _timestamp;

In DataPortal_Fetch:
dr.GetBytes("LastChanged", 0, _timestamp, 0, 8);

In Stored Procedure:
SET
    ...           
    WHERE    BookId = @id
        AND LastChanged = @lastChanged
        IF @@ROWCOUNT = 0
        RAISERROR('Row has been edited by another user', 16,1)

This post: http://forums.lhotka.net/forums/thread/8053.aspx mentions the same problem and I adjusted my code in DataPortal_Update to explicitly set the datatype of the parameter, as suggested, but I still get the 'Row has been edited by another user' error.  The database is Sql Server Express.

Any ideas?

By the way, Rocky -- I enjoyed the book and really like working with the framework so far.

dcleven replied on Friday, May 25, 2007

I think you need to set the direction of the parameter as an InputOutput, like this:

SqlParameter param = new SqlParameter("@NewTimeStamp", SqlDbType.Timestamp);

param.Direction = ParameterDirection.InputOutput;

param.Value = m_timestamp;

cm.Parameters.Add(param);

cm.ExecuteNonQuery();

m_timestamp = (byte[])cm.Parameters["@NewTimeStamp"].Value;

The above code works for me

--Doug

toddb1389 replied on Monday, May 28, 2007

That did the trick.  Thanks Doug!