What I want can be best explained by a scenario where two users are accessing the same row in a web form (where data is in disconnected objects) and the changes made by the second user overwrites the changes made by the first. In this case I want to
alert the second user while retrieving the record for editing that first user has already retrieved and is in the edit mode.
When first user is editing it then I want the second user to wait for a while which is the time gap given for any user to finish the updates. And then the second user can try for retrieving it again.
I guess this could be solved by using the timestamp column hoping that timestamp field automatically gets updated while select statements.