Re: DELETE with LIMIT (or my first hack)

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От Rob Wultsch
Тема Re: DELETE with LIMIT (or my first hack)
Дата
Msg-id AANLkTinuw5XhpMMb6quthPZ99zQmBEr5ew6be7iJ52Z=@mail.gmail.com
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Ответ на Re: DELETE with LIMIT (or my first hack)  (Marti Raudsepp <marti@juffo.org>)
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On Mon, Nov 29, 2010 at 10:50 PM, Marti Raudsepp <marti@juffo.org> wrote:
> On Tue, Nov 30, 2010 at 05:09, Jaime Casanova <jaime@2ndquadrant.com> wrote:
>> at least IMHO the only sensible way that LIMIT is usefull is with
>> an ORDER BY clause with make the results very well defined...
>
> DELETE with LIMIT is also useful for deleting things in batches, so
> you can do large deletes on a live system without starving other users
> from I/O. In this case deletion order doesn't matter (it's more
> efficient to delete rows in physical table order) -- ORDER BY isn't
> necessary.
>
> Regards,
> Marti
>

++

I have a lot of DELETE with LIMIT in my (mysql) environment for this reason.


-- 
Rob Wultsch
wultsch@gmail.com


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