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Desirable Properties of Decomposition

  1. We'll take another look at the schema

     Lending-schema = (bname, assets, bcity, loan#, cname, amount)

    which we saw was a bad design.

  2. The set of functional dependencies we required to hold on this schema was:

     bname  tex2html_wrap_inline1526  assets bcity

    loan# tex2html_wrap_inline1526 amount bname

  3. If we decompose it into

     Branch-schema = (bname, assets, bcity)

    Loan-info-schema = (bname, loan#, amount)

    Borrow-schema = (cname, loan#)

    we claim this decomposition has several desirable properties.

Osmar Zaiane
Thu Jun 18 12:56:34 PDT 1998