From: | Ron Mayer <rm_pg(at)cheapcomplexdevices(dot)com> |
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To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Subject: | Re: TB-sized databases |
Date: | 2007-12-07 20:46:21 |
Message-ID: | 4759B11D.1030201@cheapcomplexdevices.com |
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Lists: | pgsql-performance |
Tom Lane wrote:
> Ron Mayer <rm_pg(at)cheapcomplexdevices(dot)com> writes:
>> Tom Lane wrote:
>>> There's something fishy about this --- given that that plan has a lower
>>> cost estimate, it should've picked it without any artificial
>>> constraints.
One final thing I find curious about this is that the estimated
number of rows is much closer in the "offset 0" form of the query.
Since the logic itself is identical, I would have expected the
estimated total number of rows for both forms of this query to
be identical.
Any reason the two plans estimate a different total number of rows?
(explain statements for the two forms of the same query
from earlier in the thread here:
http://archives.postgresql.org/pgsql-performance/2007-12/msg00088.php )
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