Re: Updating histogram_bounds after a delete

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От Kevin Grittner
Тема Re: Updating histogram_bounds after a delete
Дата
Msg-id 4D81DCCE020000250003BA27@gw.wicourts.gov
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Ответ на Re: Updating histogram_bounds after a delete  (Kenneth Marshall <ktm@rice.edu>)
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Kenneth Marshall <ktm@rice.edu> wrote:

> I think this is it:
>
>
http://archives.postgresql.org/pgsql-committers/2010-01/msg00021.php

Looks like it.  Based on the commit date, that would be a 9.0
change.  Based on the description, I'm not sure it fixes Derrick's
problem; the workaround of explicitly using min() for the low end of
a range may need to be a long-term approach.

It does seem odd, though, that the statistics would be off by that
much.  Unless the query is run immediately after a mass delete,
autovacuum should be fixing that.  Perhaps the autovacuum
improvements in later releases will solve the problem.  If not, an
explicit ANALYZE (or perhaps better, VACUUM ANALYZE) immediately
after a mass delete would be wise.

-Kevin

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