Re: POSIX Regular Expression question

On Mon, Sep 05, 2005 at 04:19:28PM +0200, Peter Eisentraut wrote:
> Am Montag, 5. September 2005 15:57 schrieb Aldor:
> > I want to get out a string only with characters A-Za-z.
> > Any idea how to do this in Postgres with POSIX Regex?
>
> Presumably,
>
> colname ~ '^[A-Za-z]*$'
>
> If you want to be independent of locale issues, then you'd have to enumerate
> all the letters instead of using a range specification.

Note that [:alpha:] and such character classes are defined by POSIX to
be locale independent:

alvherre=# select 'á' ~ '[a-z]';
?column?
----------
f
(1 fila)

alvherre=# select 'á' ~ '[[:alpha:]]';
?column?
----------
t
(1 fila)

--
Alvaro Herrera -- Valdivia, Chile Architect, www.EnterpriseDB.com
"En las profundidades de nuestro inconsciente hay una obsesiva necesidad
de un universo lógico y coherente. Pero el universo real se halla siempre
un paso más allá de la lógica" (Irulan)