From: Tom Lane <tgl@sss.pgh.pa.us>
To: hmoustaid.mships@gmail.com
cc: pgsql-docs@lists.postgresql.org
Subject: Re: constraint_exclusion not working correctly
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 <172364933910.395942.11462602571152584372@wrigleys.postgresql.org>
References: <172364933910.395942.11462602571152584372@wrigleys.postgresql.org>
Comments: In-reply-to PG Doc comments form <noreply@postgresql.org>
	message dated "Wed, 14 Aug 2024 15:28:59 -0000"
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Date: Thu, 15 Aug 2024 22:26:19 -0400
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PG Doc comments form <noreply@postgresql.org> writes:
> I have noted that, in order for constraint exclusion to work correctly when
> partitioning using inheritance, we must use simple comparisons in check
> constraints (e.g., =, >=, <=, BETWEEN, etc.). If conditions are combined
> using AND or OR, unnecessary partitions may be scanned.

> Therefore, the example in this PostgreSQL documentation will not work
> properly with constraints like CHECK (logdate >= DATE '2006-02-01' AND
> logdate < DATE '2006-03-01'). However, it will work with the BETWEEN
> operator.

The example in the documentation works perfectly well for me.

			regards, tom lane