Re: Query optimizer 8.0.1 (and 8.0) - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Query optimizer 8.0.1 (and 8.0)
Date
Msg-id 17745.1107736435@sss.pgh.pa.us
Whole thread Raw
In response to Query optimizer 8.0.1 (and 8.0)  (pgsql@mohawksoft.com)
Responses Re: Query optimizer 8.0.1 (and 8.0)  (pgsql@mohawksoft.com)
Re: Query optimizer 8.0.1 (and 8.0)  (Greg Stark <gsstark@mit.edu>)
List pgsql-hackers
pgsql@mohawksoft.com writes:
> One of the things that is disturbing to me about the analyze settings is
> that it wants to sample the same number of records from a table regardless
> of the size of that table.

The papers that I looked at say that this rule has a good solid
statistical foundation, at least for the case of estimating histograms.
See the references cited in analyze.c.
        regards, tom lane


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