From: "Ries van Twisk" <ries@jongert.nl>
To: "'Tom Lane'" <tgl@sss.pgh.pa.us>
Cc: <pgsql-sql@postgresql.org>
Subject: Re: UNIQUE boolean: only one row may be "true" 
Date: Wed, 7 May 2003 09:34:46 +0200
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Tom,

> FWIW, I'd go with the unique partial index too.  It's a very efficient
> solution.  But it's not portable :-(.  I'd be interested to hear what
> people would do to solve this problem in bog-standard SQL.

I do it by creating a trigger (on a INSERT or UPDDATE trigger) which call's
a pgsql function.

Not very eficcient but I don't have that many inserts for the tables on a
regular base (100 a day at the max...)

Ries


> -----Oorspronkelijk bericht-----
> Van: pgsql-sql-owner@postgresql.org
> [mailto:pgsql-sql-owner@postgresql.org]Namens Tom Lane
> Verzonden: woensdag 7 mei 2003 5:01
> Aan: Randall Lucas
> CC: Michael Teter; pgsql-sql@postgresql.org
> Onderwerp: Re: [SQL] UNIQUE boolean: only one row may be "true"
>
>
> Randall Lucas <rlucas@tercent.net> writes:
> > Do you have any suggestions on how this might
> > better be implemented?  It seems to me that with a partial
> index, there
> > is not too much overhead and it doesn't seem too offensively
> > un-boycecoddean.
>
> FWIW, I'd go with the unique partial index too.  It's a very efficient
> solution.  But it's not portable :-(.  I'd be interested to hear what
> people would do to solve this problem in bog-standard SQL.
>
> 			regards, tom lane
>
>
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