To: <pgsql-general@postgresql.org>
Subject: Re: [pgsql-advocacy] Oracle buys Innobase
References: 
 <CC1CF380F4D70844B01D45982E671B239E8BEC@mtxexch01.add0.masergy.com>
From: Doug Quale <quale1@charter.net>
Date: Thu, 20 Oct 2005 15:29:22 -0500
In-Reply-To: 
 <CC1CF380F4D70844B01D45982E671B239E8BEC@mtxexch01.add0.masergy.com>
	(Guy Rouillier's message of "Wed, 19 Oct 2005 16:07:23 -0500")
Message-ID: <878xwokk4d.fsf@charter.net>
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"Guy Rouillier" <guyr@masergy.com> writes:

> Doug Quale wrote:
>> 
>> # select 'a'::char(8) = 'a '::char(8);
>>  ?column?
>> ----------
>>  t
>> (1 row)
>> 
>> Trailing blanks aren't significant in fixed-length strings, so the
>> question is whether Postgresql treats comparison of varchars right. 
>
> This result is being misinterpreted.   
>
> select length('a'::char(8)) ==> 1
> select length('a '::char(8)) ==> 1
>
> So it isn't that the two different strings are comparing equal.  The
> process of casting them to char(8) is trimming the blanks, so by the
> time they become fixed length strings, they are indeed equal.

Huh??? What version of PG are you using?  On 7.4.9,


test=# select length('a'::char(8));
 length 
--------
      8
(1 row)

test=# select length('a '::char(8));
 length 
--------
      8
(1 row)

The truncation you describe would simply be wrong.