This isn't safe for any kind of multi-user use. Say user A is in the middle of a transaction and asks for a sequence. The global id is incremented, but since A has not completed the transaction, he does not commit. Now B comes along and asks for a sequence. He sees the previous value of the global id, which is then incremented and given to him -- the same value A had got!

This can only be safe if the sequence-pulling is atomic, for example if it is done on separate database handles than the ones A and B use for the rest of their applications.

In reply to Re^2: Sequences, last_insert_id, SQLite, and Oracle by gaal
in thread Sequences, last_insert_id, SQLite, and Oracle by gaal

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