On Wed, Aug 28, 2002 at 03:36:06PM +0100, Mark McRitchie wrote:
> Now, I'm not 100% convinced that this syntax will work (I use MySQL) but:
>
> if you put an entry in your exim_user_aliases with the PostgreSQL wildcard
> character in it (% under MySQL, not sure about PostgreSQL) as the localpart
> eg
> | id | localpart | destination | owner
> | ----+-----------+----------------------+-------------
> | 24 | % | ssmeenk@??? | domain.tld
>
> and then if you use the 'LIKE' operator instead of '=' in your where clause,
> but reverse the bits so that instead of matching the DB against the
> ${local_part} your matching the opposite way round:
>
> SELECT destination FROM exim_user_aliases WHERE
> lower('${quote_pgsql:$local_part}') LIKE lower(localpart) = AND lower(owner)
> = lower('${quote_pgsql:$domain}'
Yuk. It works on Oracle too, although I personally think it's nasty in
concept. Another possibility is:
(note that I've removed lower() calls and $quote_.. clauses for clarity)
SELECT destination FROM user_aliases
WHERE localpart IN ('$local_part', '%') AND domain = '$domain'
AND rownum <= 1
which does two unique scans rather than a range scan. If you have enough
entries to justify using an index at all, mind you :}
SRH
--
Steve Haslam Reading, UK araqnid@???
Debian GNU/Linux Maintainer araqnid@???
but I won't admit to needing you
I'll never say that's true, not to you [sister machine gun]
