From: Joe Conway <mail@joeconway.com>
To: Markus Bertheau <twanger@bluetwanger.de>
Cc: pgsql-sql@postgresql.org
Subject: Re: Empty array IS NULL?
Date: Mon, 28 Jun 2004 09:26:27 -0700
Message-ID: <40E046B3.2070603@joeconway.com> (raw)
In-Reply-To: <1088438514.3239.97.camel@dicaprio.akademie1.de>
References: <1088438514.3239.97.camel@dicaprio.akademie1.de>
Markus Bertheau wrote:
> is the empty array representable in PostgreSQL, and is it
> distinguishable from NULL?
Yes, and yes.
regression=# select '{}'::int[];
int4
------
{}
(1 row)
regression=# select NULL::int[];
int4
------
(1 row)
Since NULL array elements are not currently supported, attempting to
construct an array with a NULL element results in NULL, not an empty array.
Joe
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To: pgsql-sql@postgresql.org
Cc: mail@joeconway.com, twanger@bluetwanger.de
Subject: Re: Empty array IS NULL?
In-Reply-To: <40E046B3.2070603@joeconway.com>
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