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copied!<p>This is the problem inherent in a stateless application. If a user abandons the session, by just walking off or simply closing the browser, there is no good way for you to know <em>for sure</em> that the session should be closed. The best solution that I have come up with is to use a timestamp as the locking field then regularly poll for records that have been locked for "too long". Not a perfect solution but it should address 90%+ of your issues.</p> <p><em>edit after comment from OP:</em></p> <p>@ARB, Transactions are used to execute a sequence of SQL statements that may potentially need to be rolled back. It is typically reserved for save actions (inserts, updates & deletes). You can not "roll back" a select statement (nothing to 'undo'). So wrapping your btnNext action (a select) and your btnSubmit action in a transaction is not needed. Additionally when I have used transactions it has been in the form of a single sequence of commands. I can't say <em>I know</em> you can't join a transaction in the middle, but I have never seen it done. Depending on the complexity of your save function following btnSubmit may be a good place to use a transaction, but then only if you are saving to multiple tables.</p> <p><em>In summary</em>: </p> <p>Because of the stateless nature of web apps, and the inability to 'force' a user to close their session 'gracefully' you need a mechanism that 'unlocks' a record that has been locked for 'too long'.</p> <p>Because there is nothing to 'roll back' in your btnNext action (a select command) there is no reason to include this in a transaction. If you wish to isolate your btnSubmit (save action) then that may be useful. </p>

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