Re: Prepared statements considered harmful
От | Gregory Stark |
---|---|
Тема | Re: Prepared statements considered harmful |
Дата | |
Msg-id | 87hczrippj.fsf@stark.enterprisedb.com обсуждение исходный текст |
Ответ на | Re: Prepared statements considered harmful ("Jeroen T. Vermeulen" <jtv@xs4all.nl>) |
Ответы |
Re: Prepared statements considered harmful
Re: Prepared statements considered harmful |
Список | pgsql-hackers |
"Jeroen T. Vermeulen" <jtv@xs4all.nl> writes: > On Fri, September 1, 2006 16:53, Martijn van Oosterhout wrote: > >> Interesting thought. It might be worth trying. But my big question: is >> all this testing and counting actually going to be faster than just >> replanning? Postgresql's planner is not that slow. > > In the best case (which of course would have to be very frequent for any > of this to matter in the first place) it's mainly just a short loop > comparing the call's parameter values to their counterparts stored with > the plan and update those two-bit confidence counters. You wouldn't > *believe* how simple you have to keep these things in processor > architecture. :-) I think the slow part is trying to figure out whether to count the current call as a hit or a miss. How do you determine whether the plan you're running is the best plan without replanning the query? -- Gregory Stark EnterpriseDB http://www.enterprisedb.com
В списке pgsql-hackers по дате отправления: