Re: sequence locking

"Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov> writes:
> Andres Freund <andres(at)anarazel(dot)de> wrote:
>> - Its impossible to emulate proper locking yourself because
>> locking is not allowed for sequences

>> Any arguments against allowing it again? It seems to have been
>> allowed in prehistoric times.

If you think that it used to be allowed, it'd be a good idea to see
if you can find the archived discussions about changing it.

> It would be nice to allow it. I've had to create a dummy table just
> to use for locking a sequence (by convention).

One question is what you think the lock means. I believe for example
that taking a non-exclusive regular table lock on a sequence would not
prevent other sessions from doing nextval(); even an exclusive one would
not prevent them from doing so if they had pre-cached values.

regards, tom lane