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Message-ID: <99b656cb0708280447x4eb7c45axec01c8d0ebc6c82d@mail.gmail.com>
Date: Tue, 28 Aug 2007 12:47:45 +0100
From: "Sebastian Ritter" <ritter.sebastian@gmail.com>
To: pgsql-sql@postgresql.org
Subject: Re: Database normalization
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Hello,

>
> I have a fairly basic question about database design where im not sure
> which approach is considered correct.
>
> I have two different entities: Clients and Services. Both allow users to
> add progressive updates about the two entities.
>
> The update/message format is exactly the same for both. Should I make two
> different tables:
>
>   client_updates and service_updates
>   or
>   one table with extra columns : is_client, client_id, service_id, where
> either client_id or service_id would be null depending on the is_client
> boolean?
>
> The major problem is simply relating the foreign key in the updates table
> back to the correct entity, client or service.
>
> Regards,
> Sebastian
>
>

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<span class="gmail_quote"></span>Hello,<br><div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><br>I have a fairly basic question about database design where im not sure which approach is considered correct. 
<br><br>I have two different entities: Clients and Services. Both allow users to add progressive updates about the two entities.
<br><br>The update/message format is exactly the same for both. Should I make two different tables:<br><br>&nbsp; client_updates and service_updates <br>&nbsp; or <br>&nbsp; one table with extra columns : is_client, client_id, service_id, where either client_id or service_id would be null depending on the is_client boolean?
<br><br>The major problem is simply relating the foreign key in the updates table back to the correct entity, client or service.<br><br>Regards,<br><span class="sg">Sebastian<br><br>
</span></blockquote></div><br>

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