De.clare-a deductive database system with heterogeneous access to relational database systems

Author

Schmidt, Helmut ; Steger, Nikolaus

Author_Institution

MAD Intelligent Syst. GmbH, Munchen, Germany

fYear

1991

fDate

7-9 Apr 1991

Firstpage

108

Abstract

The deductive database system De.clare offers a tight coupling to heterogeneous relational database systems. Tight coupling means that there is no semantical gap between the evaluation and optimization strategies of the deductive database system and the corresponding strategies used by relational database systems. This could be achieved by using the bottom-up approach for computing the answer of a query to a deductive database. In particular, this bottom-up approach means that a query to a deductive database system is translated into a relational algebra expression. Then those subqueries are identified that can be evaluated on a relational database system. After the answers to these subqueries have been computed, the results are combined on a relational database system which offers an extended relational algebra and finally the answer of the original query is computed

Keywords

database theory; deductive databases; query languages; relational databases; De clare; bottom-up approach; deductive database system; extended relational algebra; heterogeneous access; heterogeneous relational database systems; optimization strategies; relational algebra expression; relational database systems; semantical gap; subqueries; Algebra; Arithmetic; Database systems; Deductive databases; Intelligent systems; Relational databases; Turning;

fLanguage

English

Publisher

ieee

Conference_Titel

Interoperability in Multidatabase Systems, 1991. IMS '91. Proceedings., First International Workshop on

Conference_Location

Kyoto

Print_ISBN

0-8186-2205-9

Type

conf

DOI

10.1109/IMS.1991.153692

Filename

153692