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	Tue, 4 Jun 2002 10:33:42 -0400
From: Jan Wieck <janwieck@yahoo.com>
Message-Id: <200206041433.g54EXgE04836@saturn.janwieck.net>
Subject: Re: Is this a feature ?
In-Reply-To: <200206041018.24328.david.bouriaud@ac-rouen.fr> from David
	BOURIAUD at "Jun 4, 2002 10:18:24 am"
To: David BOURIAUD <david.bouriaud@ac-rouen.fr>
Date: Tue, 4 Jun 2002 10:33:42 -0400 (EDT)
Cc: pgsql-sql@postgresql.org
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David,

    yes, this is a feature, and no, we will not change it.

    You're  missing  the difference between empty strings or zero
    value and SQL NULL values. Do you know (hint,  hint)  how  to
    use the mailing list archives?


Jan

David BOURIAUD wrote:
> Hi the list !
> I've read the docs, and found that you could concatenate two or more strings
> in one select statement like this :
> select
>    civ || name || forname as identity
> from
>    person;
>
> This just works fine and returns rows with only one column named identity.
> So far, if one of the fields (civ, name or forname) is null, identity is
> null... That doesn't seems right, since it means that 1+2+0 = 0 !!!!
> Has anybody else seen the same strange behaviour ? And is there a way to work
> this around ?
> Please, don't answer me to use the function textcat (text, text), since it
> behaves the same and makes queries quite unreadeable...
> eg.
> select
>    textcat ( textcat (civ, name), forname) as identity
> from person;
> is quite readeable, but when you add fields separator, it isn't.
> --
> David BOURIAUD
> ----------------------------------------------------------
> In a world without walls or fences, what use do we have
> for windows or gates ?
> ----------------------------------------------------------
> ICQ#102562021
>
>
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