Re: Locking & concurrency - best practices

On Jan 14, 2008, at 4:57 PM, Adam Rich wrote:

>>
>>  From what I can tell, this kind of roll-your-own application level
>> locking system is exactly what advisory locks are for.  Search the
>> archives for the last couple of weeks as I remember someone posting
>> some really helpful functions to assist in using advisory locks.
>>
>> Erik Jones
>
> Yes & No... it depends on the lifetime of the locks you need.  The new
> advisory locks in postgres only live for the duration of your session.
> The ones Andy describes will live past session end, connection end,
> even through database restarts.  And if you're using replication or
> log shipping, the locks will be propagated to partner databases
> as well.
>
> If you need your locks to live past session end, the advisory locks
> won't help you.

Good point.

Erik Jones

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