Message-ID: <509F7CD7.1080009@2ndQuadrant.com>
Date: Sun, 11 Nov 2012 18:24:23 +0800
From: Craig Ringer <craig@2ndQuadrant.com>
Organization: 2nd Quadrant
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To: pantelis vlachos <vlachos83@gmail.com>
CC: pgsql-sql@postgresql.org
Subject: Re: find sudstring on text (data type) field failure
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On 11/07/2012 04:36 PM, pantelis vlachos wrote:
> I was trying to find a substring on a text (data type) column like
> 'cat foo dog ...'.
> I use the query below
> SELECT id FROM table WHERE name LIKE '% foo %';
> Sometimes the query return with nTuples=0 but there are matching rows.
> On retry, the query return with expected results. Any ideas;
>
> (postgres ver 9.2, libpq - C Library)

Nowhere near enough information. I'd say you have concurrency issues; at
the time you ran the query there weren't actually matching rows. See if
you can put together a test case that demonstrates the issue, or follow
up with a lot more detail.