Re: Another view on analysis and ER
From: Jon Heggland <jon.heggland_at_ntnu.no>
Date: Fri, 07 Dec 2007 09:42:27 +0100
Message-ID: <fjb12b$jnt$2_at_orkan.itea.ntnu.no>
>> Bingo! That's the big problem with the literature on ER. Many ER
>> proponents use ER as if it were a design artifact. I think that 's a
>> misapplication of the artifact, and I'm pretty sure Peter Chen would agree.
>> If one is designing a relational system (including but not limited to a
>> relational database) then using the relational model to capture the design
>> is a much better idea.
Date: Fri, 07 Dec 2007 09:42:27 +0100
Message-ID: <fjb12b$jnt$2_at_orkan.itea.ntnu.no>
Quoth rpost:
> David Cressey wrote:
>> Bingo! That's the big problem with the literature on ER. Many ER
>> proponents use ER as if it were a design artifact. I think that 's a
>> misapplication of the artifact, and I'm pretty sure Peter Chen would agree.
>> If one is designing a relational system (including but not limited to a
>> relational database) then using the relational model to capture the design
>> is a much better idea.
> > Well, that reflects what "we" teach: make a model in ER then convert it > into a logical relational design. I thought it was how ER is *always* used.
But this conversion is fairly mechanical. Is "design" in this case just
the little bit of human input that enters this process?
--
Jon
Received on Fri Dec 07 2007 - 09:42:27 CET