Re: About Entity Relation Diagram

From: Alan <not.me_at_rcn.com>
Date: Fri, 17 Dec 2004 17:14:25 -0500
Message-ID: <32h42iF3mmlqtU1_at_individual.net>


"Silver" <argytzak_at_med.auth.gr> wrote in message news:cpvc1c$7mi$1_at_nic.grnet.gr...
> Hi again,
>
> before I continue, I must thank you all for replying to this post !!
>
> After reading some things I begin to get a grasp of how things works.with
> database modelling. The question I have now has to do with the
> implementation of the database.
>
> As you remember (I hope so...) it's about a dating site.
> I have to include in the entity member a whole lot of info, such as
> eyeColor, hairColor, bodyType, etc. This can be done with two ways
>
> 1. I have a table called "EyeColor" with the columns eyeColodCode and
> Description.
> I then include in the entity member the foreign key eyeColorCode
>
> 2. I introduce a third table (one is Member, two is EyeColor) where I list
> the memberID and the eyeColorCode.
>
> Which of the above implementation is better? The 2. involves 3 tables but
it
> seems to offer greater flexibility in making queries.
>
> Thanks!!
>
>

Method 2 is going overboard. Method 1 is better. Just be sure you list "Violet" as an eye color, or Elizabeth Taylor could not register. You should also include something like "Multi-colored", as well as "Bi-colored" Multi covers people whose eyes have multiple colors (hazel and green, for example, is not uncommon). You also run into people who have different color eyes, usually one blue and one green (bi-colored?). Received on Fri Dec 17 2004 - 23:14:25 CET

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