Program Analysis for Conversion from a Navigation to a Specification Database Interface

The conversion of database application programs is investigated when migration is required from a system with navigation (CODASYL-like) db interface to a system with specification db interface but the database semantics is not changed. We propose an analysis technique of the source program which heavily relies on program control flow. When the program semantics in analyzed from the point of view of data usage, the db statements appearing in the program are associated with one or more semantic record access patterns. A technique is given for analyzing these multiple associations and combining the access patterns into db queries. Decompilable programs are those which have reducible flow graphs.