Analysis of the context dependency of CODASYL find-statements with application to a database program conversion

Abstract

The CODASYL database (db) statements m an application program can have one or more different semantics associated with It, dependmg on the path through which the execution reaches that statement This makes the CODASYL operations m a db program context dependent The previous works on the conversion of db programs from the CODASYL record at a time mterface to the set at a time mterface of the relational model consider only a limited class of programs where each db statement in the program is assumed to have a unique semantic interpretation In this paper, we first define a framework for analyzing the multiple semantics of the CODASYL operations and their context dependencies We then show how to convert a CODASYL db program which contains statements havmg ambiguous, multiply-defined semantics In principle, the method described here allows us to convert all CODASYL db programs. © 1985, ACM. All rights reserved.