Data Model:

Aaron Watters aaron.watters at gmail.com
Mon Apr 13 04:46:34 CEST 2009


On Apr 12, 10:14 pm, Anthony <alantho... at gmail.com> wrote:
> I'm struggling on whether or not to implement GroupItem (below) with
> two separate models, or with one model that has a distinguishing key:
>
> Given:
> class ParentGroup:
>     a group of values represented by class GroupItem
>
> class ChildGroup:
>     a group of values represented by class GroupItem
>     foreign-key to ParentGroup (many Children sum to one Parent)
>
> Option A:
> class GroupItem:
>     foreign-key to ParentGroup
>     foreign-key to ChildGroup
>     GroupItemType in (ParentItem, ChildItem)
>     value
>     value-type
>
> Option B:
> class ParentGroupItem
>     foreign-key to ParentGroup
>     value
>     value-type
>
> class ChildGroupItem
>     foreign-key to ChildGroup
>     value
>     value-type
>
> What are my considerations when making this decision?
>
> Thanks!

It looks to me that the two designs
might be useful for different
purposes.  What are you trying to do?

  -- Aaron Watters

====
whiff.sourceforge.net
http://aaron.oirt.rutgers.edu/myapp/root/misc/erdTest




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