Christopher Smith <x@xman.org> writes:
>> Um ... surely that should be "if count > 0" ? Or was that just a
>> transcription error?
>>
>> This approach certainly ought to work as desired given the exclusive
>> lock, so a silly typo seems like a plausible explanation...
> Sorry, it is indeed a transcription error (sadly).
Oh well. The next thought, given that you mention threads, is that
you've got multiple threads issuing commands to the same backend
connection; in which case the interlocking you think you have doesn't
exist at all...
regards, tom lane