Q:

How can we handle concurrency errors in LINQ to SQL? 

How can we handle concurrency errors in LINQ to SQL? 

A:

One way is by setting the modes on each column for how it participates in conflict checking.  There are three options: Always, Never & WhenChanged
For more info, check here and here
Also an option is using the ConflictMode parameter to SubmitChanges (one of ConflictMode. ContinueOnConflict or ConflictMode. FailOnFirstConflict.  If you set it to the former, the commit will throw when complete, but you will have a collection of failed submissions for further processing... see this answer for more info.