This might be handy:
http://www.databasejournal.com/img/email_val.sql
> -----Original Message-----
> From: pgsql-general-owner@postgresql.org [mailto:pgsql-general-
> owner@postgresql.org] On Behalf Of Andrus
> Sent: Wednesday, October 19, 2005 11:12 AM
> To: pgsql-general@postgresql.org
> Subject: [GENERAL] Select all invalid e-mail addresses
>
> I have a database of e-mail addresses.
>
> I want to select the email addresses which are not valid:
>
> do not contain exactly one @ character,
> contain ; > < " ' , characters or spaces etc.
>
> What is the WHERE clause for this ?
>
> Andrus.
>
>
>
> ---------------------------(end of
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> TIP 6: explain analyze is your friend