Re: Sub-Entities in Designer/2000

walsh_at_womex.com wrote:
>
> It's been a while since I used Designer/2000 so this question might
> sound silly to some.
>
> Can anyone give me a synopsis of how Designer/2000 translates sub/super
> entities into tables at generate time.
>
> I have an entity person which holds the common data for all people on
> our database (both customers and employees) and an entity employee which
> holds additional information such as vacation entitlement etc. My
> feeling is that employee is a sub-entity of person, is this correct in
> the D2K context and if so what is the likely table structure that will
> be created.
>
> thanks in advance
> --
> regards,
>

Look into the Help of Des2K for a complete explanation how to implement different sub-type situations. I have Des2K 1.3.2 on my NT and you can find what I'm talking about by bringing up the Contents Help topic and click on the Database Design Wizard. 'Surf' around the topics there. You'll find plenty on sub and super types. Look under 'Principles of Database Design' for a Sub-Type link and read on. The topic you want to eventually find is 'Deciding How to Implement Entity Sub-types'. Check out the links under this topic.  

John Caputo                              Lawrence Livermore
Email: caputo1_at_llnl.gov                    National Laboratory
Phone: (510) 422-5262                    P.O.Box 808, L-650
Mon-Thu  7:30 AM-5:30 PM - Off Fri       Livermore, CA   94551