Date: Wed, 3 Mar 2010 16:19:00 +0100
From: Louis-David Mitterrand <vindex+lists-pgsql-sql@apartia.org>
To: pgsql-sql@postgresql.org
Subject: Re: check constraint on multiple tables?
Message-ID: <20100303151900.GA19735@apartia.fr>
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References: <20100303150227.GA18661@apartia.fr>
	<396486431003030714s48b239e2ub8b58a49b9aa29e4@mail.gmail.com>
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On Wed, Mar 03, 2010 at 07:14:29AM -0800, Richard Broersma wrote:
> On Wed, Mar 3, 2010 at 7:02 AM, Louis-David Mitterrand
> <vindex+lists-pgsql-sql@apartia.org> wrote:
> 
> 
> > What is the best solution? Adding an id_ship to 'cabin'? Or check'ing
> > with a join down to 'ship'? (if possible).
> 
> Can you post simplified table definitions for the relations involved?

Sure, here they are:

CREATE TABLE ship (
    id_ship serial primary key,
    ship_name text unique not null
);

CREATE TABLE cabin_type (
    id_cabin_type serial primary key,
    id_ship integer references ship,
    cabin_type_name text,
    cabin_type_code text,
	unique(cabin_type_code, id_ship)
);

CREATE TABLE cabin_category (
    id_cabin_category serial primary key,
    id_cabin_type integer references cabin_type,
    cabin_cat_name text,
    cabin_cat_code text,
	unique(cabin_cat_code, id_cabin_type)
);

CREATE TABLE cabin (
    id_cabin serial primary key,
    id_cabin_category integer references cabin_category,
    cabin_number integer not null,
	unique(id_cabin_category, cabin_number)
);