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Re: Pizza Example

From: Alfredo Novoa <alfredo_at_ncs.es>
Date: Sat, 24 Apr 2004 13:31:00 GMT
Message-ID: <408a6adc.400025@news.wanadoo.es>


On Fri, 23 Apr 2004 14:41:27 -0400, "Laconic2" <laconic2_at_comcast.net> wrote:

>The ER model was such a thing when I first started working with databases.
>Most of the existing databases were built on the Network (CODASYL) model,
>and many of the new databases were to be built on the relational model. It
>turns out that, if you have a good ER model of the data requirements, this
>"common model" can be turned into either a CODASYL model or a Relational
>model, as you choose.

But if you have an ER model you don't have a database design. The modeling capabilities of the ER model are very very poor and it leads to poor relational database designs.

You can not turn a relational database design in a ER model in almost all cases.

Regards
  Alfredo Received on Sat Apr 24 2004 - 08:31:00 CDT

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