From: Rob Sargent <robjsargent@gmail.com>
To: pgsql-sql@postgresql.org
Subject: Re: setting the where clause
Date: Wed, 10 Jun 2009 09:13:06 -0600
Message-ID: <4A2FCD82.7000206@gmail.com> (raw)
In-Reply-To: <347.1244643554@sss.pgh.pa.us>
References: <200906100519.34171.jfabiani@yolo.com>
<347.1244643554@sss.pgh.pa.us>
Tom Lane wrote:
> johnf <jfabiani@yolo.com> writes:
>
>> I'm am programming in python using the Dabo modules. www.dabodev.com if your
>> interested. Dabo is a framework that provides an easy way to build desktop
>> app's. To clear a data entry form. I have been setting the where clause
>> to "where 1=0". This of course retrieves 0 records and my form will display
>> nothing. It has been suggested that it might be better to set the where
>> clause to a primary key value that does not exist in the table "where PK
>> = -9999999".
>>
>
> Whoever said that doesn't know what they're talking about. It's not
> faster (because it forces an actual index probe to happen) and it's not
> safer (what if one day that PK value exists?).
>
> I'd personally go with "where false"; why not say what you mean rather
> than forcing humans and computers to deduce that the condition is
> constant false?
>
> regards, tom lane
>
>
Of course you would do the world a favour if you wrote a client-side
clear-the-screen routine that didn't pester the net and the server
un-necessarily.
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To: pgsql-sql@postgresql.org
Cc: robjsargent@gmail.com
Subject: Re: setting the where clause
In-Reply-To: <4A2FCD82.7000206@gmail.com>
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