Re: why do optimizer parameters have to be set manually?
От | Christopher Browne |
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Тема | Re: why do optimizer parameters have to be set manually? |
Дата | |
Msg-id | 60n09q9bqg.fsf@dev6.int.libertyrms.info обсуждение исходный текст |
Ответ на | why do optimizer parameters have to be set manually? ("Marinos J. Yannikos" <mjy@geizhals.at>) |
Ответы |
is it possible to get the optimizer to use indexes with a like
clause
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Список | pgsql-performance |
mjy@geizhals.at ("Marinos J. Yannikos") writes: > it seems to me that the optimizer parameters (like random_page_cost > etc.) could easily be calculated and adjusted dynamically be the DB > backend based on the planner's cost estimates and actual run times for > different queries. Perhaps the developers could comment on that? Yes, it seems like a Small Matter Of Programming. http://wombat.doc.ic.ac.uk/foldoc/foldoc.cgi?SMOP In seriousness, yes, it would seem a reasonable idea to calculate some of these values a bit more dynamically. I would be inclined to start with something that ran a workload, and provided static values based on how that workload went. That would require NO intervention inside the DB server; it could be accomplished simply by writing a database script. Feel free to contribute either a script or a backend "hack"... -- let name="cbbrowne" and tld="libertyrms.info" in String.concat "@" [name;tld];; <http://dev6.int.libertyrms.com/> Christopher Browne (416) 646 3304 x124 (land)
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