Hitherto, most relational database design methods are based
on functional dependencies (FDs) and multivalued dependencies
(MVDs). Full mappings are proposed as an alternative to FDs and
MVDs. A mapping between any two sets, apart from being one-one,
many-one, or many-many, is either total or partial on the source
and target sets. An 'into' mapping on a set, expresses the fact
that an element in the set may not be involved in the
mapping. An 'onto' mapping on a set is total on the set. A
many-many (into,onto) mapping from set A to set B is written as
A[sup=i] m----n B[sup=o].
The mappings incorporate more semantic information into data dependency specification. It is shown, informally, that the full mappings are more expressive than FDs and MVDs. Transformation rules, to generate Boyce-Codd normal form and projection-join normal form schemas from the full mappings, are defined. The full mapping/transformation rules provide a discipline for modeling nonfunctional relationships, within a synthetic approach. / Science, Faculty of / Computer Science, Department of / Graduate
| Identifer | oai:union.ndltd.org:UBC/oai:circle.library.ubc.ca:2429/23201 |
| Date | January 1982 |
| Creators | Ola, Adegbemiga |
| Source Sets | University of British Columbia |
| Language | English |
| Detected Language | English |
| Type | Text, Thesis/Dissertation |
| Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
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