In this paper, the authors describe a custom relational algebra query software environment that enables database instructors to teach relational algebra programming. Instead of defining query ...

Abstract: Extensive work has recently been done on the evaluation of positive queries on probabilistic databases. The case of queries with negation has notoriously been left out, since it raises ...

There are two types of relational database manipulation language: procedural and assertional. A procedural language is one in which a query is expressed through a sequence of operations. This category ...

Abstract: In this paper we present a theory of relational database systems based on the partition lattice, which represents a new mathematical approach to the structure of relational database systems.

A interpreter which takes relational algebra expression as input from the user, automatically converts them to SQL queries, executes the queries on the database server, and outputs the results of the ...

This application provides a graphical user interface for performing relational algebra operations on user-defined relations. A dynamic table allows users to input tuple data hassle free and without ...

ABSTRACT: This paper reviews the research literature with respect to the contributions to the students’ difficulties in their algebra learning in order to understand the students’ difficulties in ...