Can you convince a DataContext to treat a column as always dirty?

Question

Is there a way to force LINQ-to-SQL to treat a column as dirty? Globally would suffice....

Basically, I\'ve got a problem with some audit code on a legacy system tha

Answer 1

The following works for me. Note though that I'm using the linq2sql provider from DevArt, but that may not matter:

MyDataContext dc = new MyDataContext();

Message msg = dc.Messages.Single(m => m.Id == 1);
Message attachingMsg = new Message();
attachingMsg.Id = msg.Id;

dc.Messages.Attach(attachingMsg);

attachingMsg.MessageSubject = msg.MessageSubject + " is now changed"; // changed
attachingMsg.MessageBody = msg.MessageBody; // not changed
dc.SubmitChanges();

This produces the following sql:

UPDATE messages SET messageSubject = :p1, messageBody = :p2 WHERE Id = :key1

So, messageBody is updated even though its value is not changed. One other change necessary for this, is that for each property (column) of my entity Message, I have set UpdatedCheck = UpdateCheck.Never, except for its ID, which is the primary key.