Message-ID: <20051028130720.jxoth8izb468k44s@www.presserv.org>
Date: Fri, 28 Oct 2005 13:07:20 -0300
From: lucas@presserv.org
To: daryl@brandywine.com
Cc: pgsql-sql@postgresql.org
Subject: Re: Fwd: Re: Referencing
References: <20051028105908.onaegu44ynnog8os@www.presserv.org>
	<43624661.7000404@brandywine.com>
In-Reply-To: <43624661.7000404@brandywine.com>
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Quoting Daryl Richter <daryl@brandywine.com>:
> It's hard to say without knowing more precisely what you are trying 
> to model, but I think this push you in the right direction:
>
>   -- This table takes the place of both SEND and BUY
>   create table activity(
>      id          serial primary key,
>      product_id  integer,     --references....
>      value       money
>   );
>
>   create table financial(
>     id          serial primary key,
>     cred_deb    smallint,
>     value       money,
>     activity_id integer references activity
>   );
>
>   create table output(
>     id            serial primary key,
>     client        integer,                 --references clientes,
>     fiscal_number varchar(30),
>     print_date    date,
>     activity_id   integer  references activity
>   );
>
>   create table input(
>     id           serial     primary key,
>     supplier     integer,                       -- references suppliers,
>     employee     varchar(30),
>     activity_id  integer    references activity
>   );
>
> And then you do the following:
>
>   create view buy
>   as
>   select
>       a.id,
>       b.id  as "input_id",
>       a.product_id,
>       a.value
>   from
>         activity a
>   join  input    b on b.activity_id = a.id;
>

Okay, but references between (output/input) and ACTIVITY tables is 1 to N.
OUTPUT/INPUT - 1
to
ACTIVITY - N.
And not N to 1 how the example.
Then the reference field need to be on "ACTIVITY (send/buy)" table.