From: Tom Lane <tgl@sss.pgh.pa.us>
To: gvim <gvimrc@gmail.com>
Cc: pgsql sql <pgsql-sql@postgresql.org>
Subject: Re: Find NOT NULLs in a group of 20 columns
Date: Mon, 10 Jan 2011 21:45:50 -0500
Message-ID: <5647.1294713950@sss.pgh.pa.us> (raw)
In-Reply-To: <4D2BBCF4.8070905@gmail.com>
References: <4D2BBCF4.8070905@gmail.com>
gvim <gvimrc@gmail.com> writes:
> I'm struggling to find anything other than a complex stored proc to do this:
> Out of a group of 20 columns return the rows in which:
> 1. Only 1 of the 20 columns IS NOT NULL
> 2. More than 1 of the 20 columns IS NOT NULL
> Any ideas?
Cast to int and add up?
SELECT ... WHERE
((col1 is not null)::int +
(col2 is not null)::int + ...
(col20 is not null)::int) = 1 -- or > 1
regards, tom lane
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To: pgsql-sql@postgresql.org
Cc: tgl@sss.pgh.pa.us, gvimrc@gmail.com
Subject: Re: Find NOT NULLs in a group of 20 columns
In-Reply-To: <5647.1294713950@sss.pgh.pa.us>
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