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#1 (**permalink**) 04-10-2008, 09:49 AM

The following bug has been logged online:

Bug reference: 2309
Logged by: Yury Don
Email address: yura@vpcit.ru
PostgreSQL version: 8.1.3
Operating system: Linux (Debian)
Description: Wrong string comparison
Details:

Looks like string comparison operators ignore spaces isnside of string.
Because of this sorting on text fields is wrong.

mdb=# select 'a z'::text>'ad'::text;
?column?
----------
t

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#2 (**permalink**) 04-10-2008, 09:49 AM

"Yury Don" <yura@vpcit.ru> writes:
> Looks like string comparison operators ignore spaces isnside of string.

It's not wrong, it's just following the rules of the locale. You should
initdb the database with LANG=C if you want plain ASCII sorting.

regards, tom lane

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#3 (**permalink**) 04-10-2008, 09:49 AM

Hi,

On Mar 09 02:00, Yury Don wrote:
> Looks like string comparison operators ignore spaces isnside of string.
> Because of this sorting on text fields is wrong.
>
> mdb=# select 'a z'::text>'ad'::text;
> ?column?
> ----------
> t

PostgreSQL relies on your locale for collation. Therefore, first you
need to check if your locale settings are working. For instance:

$ TEXT="a z\nad"
$ echo -e $TEXT | LC_COLLATE=tr_TR.iso88599 sort
ad
a z
$ echo -e $TEXT | LC_COLLATE=C sort
a z
ad

Regards.

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#4 (**permalink**) 04-10-2008, 09:49 AM

On Friday 10 March 2006 12:36, Volkan YAZICI wrote:
> Hi,
>
> On Mar 09 02:00, Yury Don wrote:
> > Looks like string comparison operators ignore spaces isnside of string.
> > Because of this sorting on text fields is wrong.
> >
> > mdb=# select 'a z'::text>'ad'::text;
> > ?column?
> > ----------
> > t
>
> PostgreSQL relies on your locale for collation. Therefore, first you
> need to check if your locale settings are working. For instance:
>
> $ TEXT="a z\nad"
> $ echo -e $TEXT | LC_COLLATE=tr_TR.iso88599 sort
> ad
> a z
> $ echo -e $TEXT | LC_COLLATE=C sort
> a z
> ad
>
>
> Regards.
>

My locale is KOI8-R and sorting in PostgreSQL corresponds to sorting in
locale. I just didn't expect that sorting will be this way ...

--
Best regards,
Yury Don

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BUG #2309: Wrong string comparison