Re: Object Inherit and Retrieve

In article <39405696.1FC8B7C1_at_ucalgary.ca>,   cfei_at_ucalgary.ca wrote:
> Hi, folks,
>
> Oracle 8 can create objects which encapsulated data and methods. I
 have two questions and hope to
> get your help:
>
> 1. how to implement the object inherit?
>
> I have a data model which organized by object inheritance hierarchy,
 like triangle and rectangle
> inherits from polygon. How to implement this data model in Oracle 8?

I don't see anything special. If you think a triangle is also a polygon, think of the textbook example of manager entity vs employee entity; if you don't think a triangle should also be a polygon (so it's only a child of the polygon category), think of the textbook example of department vs employee. In either case, you use foreign key constraint to implement their relationship.

--
Yong Huang

(yong321_at_yahoo.com)
(http://www.stormloader.com/yonghuang/)


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