C++ Neural Networks and Fuzzy Logic: Preface

Relations in Databases

A relation from this database may be the set of quintuples, (name, age, cov, lov, yov). Another may be the set

of triples, (name, ctz, lps). The quintuple (John Smith, 35, India, 4, 1994) belongs to the former relation, and

the triple (John Smith, U.S., Italian) belongs to the latter. You can define other relations, as well.

C++ Neural Networks and Fuzzy Logic:Preface

Databases and Queries

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Fuzzy Scenarios

Now the query part may be made fuzzy by asking to list young persons who recently visited Japan or India for

a few days. John Smith’s entries may or may not be included this time since it is not clear if John Smith is

considered young, or whether 1993 is considered recent, or if 3 days would qualify as a few days for the

query. This modification of the query illustrates one of three scenarios in which fuzziness can be introduced

into databases and their use.

This is the case where the database and relations are standard, but the queries may be fuzzy. The other cases

are: one where the database is fuzzy, but the queries are standard with no ambiguity; and one where you have

both a fuzzy database and some fuzzy queries.