From: Josh Berkus <josh@agliodbs.com>
To: Steve Crawford <scrawford@pinpointresearch.com>
To: Andreas Joseph Krogh <andreak@officenet.no>
To: Achilleus Mantzios <achill@matrix.gatewaynet.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: index on to_char(created, 'YYYY') doesn't work
Date: Wed, 15 Jan 2003 10:15:55 -0800
Message-ID: <web-2314974@davinci.ethosmedia.com> (raw)
In-Reply-To: <20030115171944.13CE5103E0@polaris.pinpointresearch.com>
Steve,
> BTW, I tried to create an index on the to_char function and had no
> luck -
> seems like it should work but it doesn't on 7.2.3 or 7.3.1.
That's because functional indexes can't take any arguments other than
column names. Therefore you'd need to:
CREATE FUNCTION to_year (timestamp) RETURNS varchar AS
'SELECT to_char($1, ''YYYY'');'
LANGUAGE 'sql' WITH (ISCACHABLE, ISSTRICT)
(above is 7.2.3 syntax)
Then use the to_year function in place of to_char for creating your
index.
-Josh Berkus
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To: pgsql-sql@postgresql.org
Cc: josh@agliodbs.com, scrawford@pinpointresearch.com, andreak@officenet.no, achill@matrix.gatewaynet.com
Subject: Re: index on to_char(created, 'YYYY') doesn't work
In-Reply-To: <web-2314974@davinci.ethosmedia.com>
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