Patch implements much more accuracy estimation of cost for GIN index scan than 
generic cost estimation function. Basic idea is described on PGCon-2010: 
http://www.sai.msu.su/~megera/postgres/talks/pgcon-2010-1.pdf, pages 48-54.

After discussion on PGCon, the storage of additional statistic information has 
been changed from pg_class table to meta-page of index. Statistics data is 
cached in Relation->rd_amcache to prevent frequent read of meta-page.

-- 
Teodor Sigaev                                   E-mail: teodor(at)sigaev(dot)ru
                                                    WWW: http://www.sigaev.ru/

Responses

• Re: gincostestimate at 2010-07-25 21:42:57 from Jan Urbański

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