From: Mark Fenbers <Mark.Fenbers@noaa.gov>
To: pgsql-sql@postgresql.org
Subject: default value for select?
Date: Mon, 09 May 2005 12:57:41 -0400
Message-ID: <427F9685.8050104@noaa.gov> (raw)
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I want to update a column in myTable. The value this column is set to
depends on a nested select statement which sometimes returns 0 rows
instead of 1. This is a problem since the column I'm trying to update
is set to refuse nulls. Here's a sample:<br>
<br>
update myTable set myColumn = (Select altColumn from altTable where
altColumn != 'XXX' limit 1) where myColumn = 'XXX';<br>
<br>
MyColumn cannot accept nulls, but sometimes "Select altColumn ..."
returns 0 rows, and thus, the query fails. <br>
<br>
Is there a way to set a default value to be inserted into myColumn if
and when "select altColumn ..." returns zero rows?<br>
<br>
Mark<br>
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To: pgsql-sql@postgresql.org
Cc: Mark.Fenbers@noaa.gov
Subject: Re: default value for select?
In-Reply-To: <427F9685.8050104@noaa.gov>
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