Setting a bit flag wouldn't lock the record. In fact, you don't really want to use SQL Server to 'lock' the record. What everyone is suggesting is that you use a bit field to 'pretend to lock' the record. In this case, you must add the conditional logic in to your application such that if the 'locked' bit is true, don't allow the user to modify the record.
Furthermore, Tyson's suggestion of using the UserId to indicate a lock is a little bit better because you would also know WHO locked the record. With the bit column, you would only know that the record was locked, but not who?
Does this make sense now?
-George
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