Re: Very inefficient query plan with disjunction in WHERE clause - Mailing list pgsql-performance

From Matthew Wakeling
Subject Re: Very inefficient query plan with disjunction in WHERE clause
Date
Msg-id alpine.DEB.1.10.0906011736110.4147@aragorn.flymine.org
Whole thread Raw
In response to Very inefficient query plan with disjunction in WHERE clause  (Koen Martens <pgsql@metro.cx>)
List pgsql-performance
On Mon, 1 Jun 2009, Koen Martens wrote:
> Anyway, any hints on getting this beast perform (without rewriting the
> query, that's not possible in this case due to the query being generated
> by an ORM) are welcome. I'm starting to think it is impossible, and that
> postgresql just doesn't work for this particular query+dataset.

Yeah, being bound by the ORM can be annoying. What version of Postgres is
this? Recent versions can sometimes do a bitmap index scan to satisfy an
OR constraint.

Matthew

--
 Anyone who goes to a psychiatrist ought to have his head examined.


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