From: Joe Conway <mail@joeconway.com>
To: Markus Bertheau ☭ <twanger@bluetwanger.de>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-hackers@postgresql.org
Subject: Re: [SQL] ARRAY() returning NULL instead of ARRAY[] resp. {}
Date: Mon, 06 Jun 2005 08:50:13 -0700
Message-ID: <42A470B5.8060007@joeconway.com> (raw)
In-Reply-To: <1118069699.5506.9.camel@dicaprio.akademie1.de>
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<42923762.7010708@joeconway.com>
<16774.1116907560@sss.pgh.pa.us>
<1118067445.5506.6.camel@dicaprio.akademie1.de>
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<1118069699.5506.9.camel@dicaprio.akademie1.de>
Markus Bertheau ☭ wrote:
> В Пнд, 06/06/2005 в 10:44 -0400, Tom Lane пишет:
>>Markus Bertheau =?UTF-8?Q?=E2=98=AD?= <twanger@bluetwanger.de> writes:
>>
>>>By analogy, array_upper('{}'::TEXT[], 1) should return 0 instead of
>>>NULL.
>>
>>No, that doesn't follow ... we've traditionally considered '{}' to
>>denote a zero-dimensional array.
>
> But array_upper(ARRAY(SELECT 1 WHERE FALSE), 1) should return 0,
> and array_upper(ARRAY[], 1), when the ARRAY[] syntax is supported,
> should return 0.
>
Actually, consistent with my last post, I think array_upper() on a
zero-element array should return NULL. A zero-element array has a
defined lower bound, but its upper bound is not zero -- it is really
undefined.
Joe
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Subject: Re: [SQL] ARRAY() returning NULL instead of ARRAY[] resp. {}
In-Reply-To: <42A470B5.8060007@joeconway.com>
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