Re: TODO idea - implicit constraints across child tables with a common column as primary key (but obviously not a shared index)

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Gregory Stark <stark(at)enterprisedb(dot)com>
Cc: "Andrew Hammond" <andrew(dot)george(dot)hammond(at)gmail(dot)com>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: TODO idea - implicit constraints across child tables with a common column as primary key (but obviously not a shared index)
Date: 2007-04-24 05:02:40
Message-ID: 23870.1177390960@sss.pgh.pa.us
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Gregory Stark <stark(at)enterprisedb(dot)com> writes:
> The main data from the statistics that's of interest here are the extreme
> values of the histogram. If we're not interested in any values in that range
> then we can exclude the partition entirely.

Except that there is *no* guarantee that the histogram includes the
extreme values --- to promise that would require ANALYZE to scan every
table row.

regards, tom lane

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