:D
May I give an exercise to the writer, then.
To build real optimistic concurrency functionality, the UPDATE query should 
be something like:
UPDATE Order SET OrderQty = 1 WHERE OrderID = 123 AND TimeStamp = <8 bytes>
If someone else has made a change to the record, the update would fail (no 
records updated), because the WHERE returns 0 records (because the 
TimeStamp field has changed in the meantime).

Is this something that can be done in Sequel? Removing the column, as you 
suggested, would certainly not work.

The TimeStamp field is (and should) not be part of the primary key, but it 
does behave a bit like one, if you look at the required UPDATE statement.
Microsoft has some background information on how to implement optimistic 
concurrency. This was our main source of inspiration when we built our 
database long ago.

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