Re: Update & Lack of Error Message - Mailing list pgsql-novice

From Michael Fuhr
Subject Re: Update & Lack of Error Message
Date
Msg-id 20060126225341.GA99170@winnie.fuhr.org
Whole thread Raw
In response to Update & Lack of Error Message  (<operationsengineer1@yahoo.com>)
Responses Re: Update & Lack of Error Message  (<operationsengineer1@yahoo.com>)
List pgsql-novice
On Thu, Jan 26, 2006 at 02:22:37PM -0800, operationsengineer1@yahoo.com wrote:
> i set up an update statement to update a unit's status
> from incomplete to completed.
>
> however, pgsql doesn't kick out an error message when
> i try to update something that doesn't exist.

The database has no way of knowing that a certain number of rows
updated (zero in your case) represents an error; that's something
the application knows.  An update that affects zero rows is perfectly
legitimate in many applications.

> i'm thinking about running a select to check the
> existence of the serial number before running the
> update.  that way, i can check that the serial 1.
> exists and 2. hasn't already been updated and, based
> on the result, kick out a message to the user as
> appropriate.

Your API should provide a way to get the number of rows updated.
What language and database interface are you using?

--
Michael Fuhr

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