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From: Michael Glaesemann <grzm@seespotcode.net>
Subject: Re: subtract a day from the NOW function
Date: Thu, 7 Jun 2007 16:53:03 -0500
To: "Fernando Hevia" <fhevia@ip-tel.com.ar>


On Jun 7, 2007, at 15:38 , Fernando Hevia wrote:

> Why not? I'm curious if has anything to do with performance or just =20=

> style?

Not style. Maybe performance because there's fewer function calls, =20
but primarily correctness. By using to_char you no longer have a date=97=20=

you have a text value=97and are relying on the collocation of your =20
database to compare two text values. This can lead to subtle bugs in =20
your code. Similarly, I would never use to_char to compare two integers:

SELECT 20 > 9 AS int_values
     , to_char(20, '9') > to_char(9, '9') AS text_values;

Is this what you would expect? What's the advantage to using to_char?

Michael Glaesemann
grzm seespotcode net