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Re: Pizza Example

From: Dawn M. Wolthuis <dwolt_at_tincat-group.com>
Date: Mon, 12 Apr 2004 11:53:28 -0500
Message-ID: <c5ehin$jer$1@news.netins.net>


"Laconic2" <laconic2_at_comcast.net> wrote in message news:47SdnSqBgfOsWefdRVn-uw_at_comcast.com...
> I need to ask one very basic question. I still don't really want to know
> how PICK works, but I want to understand the Pizza example better.
>
> Why are "Mozarella" and "Feta" stored in the same list, but "Mozarella"
> and "Pepperoni" are stored in different lists?

Yes, I put them there as one possible way of implementing a model where the user wants to track the type of component. You can do that the way one would do in a relational database, but sometimes it is helpful to have separate fields (attributes) for separate types of components. The data entry and the display will need to distinguish these in this way, but the database could store that information differently. To the extent that the data model is the same as the way the user thinks of the data, there is less user-defined vocabulary required.

In this case, a "raw" database query from the end-user could be LIST ORDER_ITEMS WITH CHEESE = "FETA"
to get all pizzas that have been ordered with feta cheese on them. This could help them do the analysis of whether to continue to offer that option. If the data were stored differently, the question could be somewhat less intuitive for the end-user.

> Or have I misinterpreted your display of the data in PICK format?

Nope, that was the intent. --dawn Received on Mon Apr 12 2004 - 11:53:28 CDT

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