From: terry@greatgulfhomes.com
To: 'Jan Wieck' <janwieck@yahoo.com>
To: 'Achilleus Mantzios' <achill@matrix.gatewaynet.com>
Cc: pgsql-general@postgresql.org
Cc: pgsql-sql@postgresql.org
Subject: Re: [SQL] VIEWs and FOREIGN keys
Date: Mon, 10 Jun 2002 14:49:33 -0400
Message-ID: <002801c210af$9088c980$2766f30a@development.greatgulfhomes.com> (raw)
In-Reply-To: <200206101720.g5AHKAK29836@saturn.janwieck.net>
I would just like to elaborate, and clarify if my understanding is correct:
The implication of below is that you need a trigger in the foreign key
target table on the DELETE event, so the foreign key table only lets you
delete a row if there are no other tables refering to the key you want to
delete.
Views cannot have triggers, hence cannot have a DELETE trigger, therefore
that is why the view cannot be a foreign key target table.
Terry Fielder
Network Engineer
Great Gulf Homes / Ashton Woods Homes
terry@greatgulfhomes.com
> -----Original Message-----
> From: pgsql-general-owner@postgresql.org
> [mailto:pgsql-general-owner@postgresql.org]On Behalf Of Jan Wieck
> Sent: Monday, June 10, 2002 1:20 PM
> To: Achilleus Mantzios
> Cc: pgsql-general@postgresql.org; pgsql-sql@postgresql.org
> Subject: Re: [GENERAL] [SQL] VIEWs and FOREIGN keys
>
>
> Achilleus Mantzios wrote:
> >
> > can someone have a foreign key constraint that references
> > a view??
>
> No, and this is not planned either. Remember that it is not
> only required for referential integrity to check if a key
> exists on INSERT or UPDATE to the referencing table. The
> system must guarantee that you cannot remove existing keys
> while they are referenced (or more precise perform the
> requested referential action).
>
>
> Jan
>
> --
>
> #=============================================================
> =========#
> # It's easier to get forgiveness for being wrong than for
> being right. #
> # Let's break this rule - forgive me.
> #
> #==================================================
> JanWieck@Yahoo.com #
>
>
>
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To: pgsql-sql@postgresql.org
Cc: terry@greatgulfhomes.com, janwieck@yahoo.com, achill@matrix.gatewaynet.com, pgsql-general@postgresql.org
Subject: Re: [SQL] VIEWs and FOREIGN keys
In-Reply-To: <002801c210af$9088c980$2766f30a@development.greatgulfhomes.com>
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