Re: Avoiding bad prepared-statement plans.
От | Alex Hunsaker |
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Тема | Re: Avoiding bad prepared-statement plans. |
Дата | |
Msg-id | 34d269d41002261202n492cc8bcoefa6ec77e507fb58@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: Avoiding bad prepared-statement plans. (Robert Haas <robertmhaas@gmail.com>) |
Список | pgsql-hackers |
On Fri, Feb 26, 2010 at 09:50, Robert Haas <robertmhaas@gmail.com> wrote: > On Fri, Feb 26, 2010 at 1:29 AM, Alex Hunsaker <badalex@gmail.com> wrote: >> Prepared plans + exec plan (new guc/ protocol thing): >> Use: not quite sure >> Problems: slow because it would replan every time >> Solutions: use a prepared plan with the appropriate things not >> parametrized...? >> >> [ aka we already have this, its called dont use a prepared statement ] > > The point is sometimes you'd like to replan every time, but not > reparse every time. There's no way to do that ATM. So what you save on parse time? Maybe that's worth it. I've never run the numbers nor have I seen them in this thread. I probably missed em... My _hunch_ is planning will on average take significantly longer than parse time (read in the noise of plan time).But that's unfounded :) I can certainly imagine caseswhere you have HUGE queries where the parse time too slow-- wont the plan most of the time be an order of magnitude slower? Anyway Ill stop until I get a chance to do _some_ kind of benchmarking, I'm really quite clueless here.
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