[LBSC 690] Minor clarification to homework

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William Webber

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Feb 29, 2012, 5:00:23 PM2/29/12
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Hi all!

I've modified the homework description for Homework 05 to
clarify that any many-to-many relationships must be resolved;
see the homework sheet for details.

William

Joel

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Mar 4, 2012, 1:57:46 AM3/4/12
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Is there really a way for the have the student table include "a list
of all the classes the student is in" without knowing the maximum
number of classes they can be in and listing that number of different
"class" foreign keys together?

William Webber

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Mar 4, 2012, 9:05:33 AM3/4/12
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No, you're exactly right. But this information, while it is
a characteristic of the student _entity_ (in the modelling sense),
does not need to be represented in the student _table_. This
is a (fairly mild) example of the mismatch between how things
are described in natural language and how they're implemented
in the database.

William

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