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From: David G. Johnston <[email protected]>
To: Rich Shepard <[email protected]>
Cc: [email protected] <[email protected]>
Subject: Re: DDL issue
Date: Thu, 12 Sep 2024 16:32:25 -0700
Message-ID: <CAKFQuwahuUyPAqG2hVi=uzVdRdU-jMmQ2eZizAKAxr=s_iVVDw@mail.gmail.com> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>

On Thursday, September 12, 2024, Rich Shepard <[email protected]>
wrote:

> I have one name in the people table who owns 5 different dairies with three
> different phone numbers, but all 5 have the the same email address.
>
> The five dairies each has its own name and location while the people table
> has five rows with the same last and first names and email address.
>
> Is there a way to have only one entry for the owner in the people table
> while related to five different company names? In some industries, such as
> dairy farms, this is not an unusual situation.
>

Read up on “many-to-many” data models.  In SQL they involve a linking
table, one row per bidirectional edge, in addition to the two node tables.

David J.

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