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Re: intersect performance (PG 7.1.3 vs 7.2) - Mailing list pgsql-sql

From Tom Lane
Subject Re: intersect performance (PG 7.1.3 vs 7.2)
Date
Msg-id 25651.1018107935@sss.pgh.pa.us
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In response to Re: intersect performance (PG 7.1.3 vs 7.2)  (d_nardini@btconnect.com)
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d_nardini@btconnect.com writes:
> Following are EXPLAIN dumps from each platform for both intersect and 
> union (both return the correct data on each platform).

Did you ever VACUUM ANALYZE these tables on the 7.1 box?  The statistics
estimates from that machine look suspiciously like default values.

If you did, then maybe I can credit 7.2's improved statistics machinery
with a win ;-).  But I bet the better choice of plan on the 7.2 box is
due simply to having any stats at all.

Can't help you with the RPM dependency issues, sorry.
        regards, tom lane

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