Abstract: The relational database model (RDM), proposed by Codd, has been proven to be a very useful model in many applications. The inherent of the RDM is effective for precise and unambiguous data.

Each region relation corresponds to a relational operator in TC. Each relational operator takes two forms, one unary and the other binary. The unary form, op S, generates the set of regions that bear ...

[a-zA-Z]+ { printf("\n%s is a WORD", yytext); } "==" { printf("\n%s is a RELATIONAL OPERATOR", yytext); } "!=" { printf("\n%s is a RELATIONAL OPERATOR", yytext ...

Abstract: Relational algebra is the theoretical basis of database design and queries. This paper extends our efforts on fuzzy relational algebraic operations under the so-called extended ...

A database that maintains a set of separate, related files (tables), but combines data elements from the files for queries and reports when required. The concept was developed in 1970 by Edgar Codd, ...