Re: Performance With Joins on Large Tables - Mailing list pgsql-performance

From Tom Lane
Subject Re: Performance With Joins on Large Tables
Date
Msg-id 16941.1158182624@sss.pgh.pa.us
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In response to Re: Performance With Joins on Large Tables  ("Joshua Marsh" <icub3d@gmail.com>)
Responses Re: Performance With Joins on Large Tables  ("Joshua Marsh" <icub3d@gmail.com>)
List pgsql-performance
"Joshua Marsh" <icub3d@gmail.com> writes:
>> Are the tables perhaps nearly in order by the dsiacctno fields?

> My assumption would be they are in exact order.  The text file I used
> in the COPY statement had them in order, so if COPY preserves that in
> the database, then it is in order.

Ah.  So the question is why the planner isn't noticing that.  What do
you see in the pg_stats view for the two dsiacctno fields --- the
correlation field in particular?

> The system has 8GB of ram and work_mem is set to 256MB.

Seems reasonable enough.  BTW, I don't think you've mentioned exactly
which PG version you're using?

            regards, tom lane

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