Database Uniformization Problem: A SEED/DAVID Interface

摘要

The database uniformization problem deals with creating a common user interface for a collection of heterogeneous databases. The DAVID (Distributed Access View Integrated Database) System is a database management system which is being implemented by the National Aeronautics and Space Administration to create such an interface. This paper deals with the implementation of certain routines used by the DAVID System to interface with SEED, a Codasyl database management system. Chapter 1 gives the particulars on this thesis. This includes examples of a DBL Data Description Language (DDL) Definition and a DBL Schema. This chapter defines certain terms used through the thesis, explains in greater detail the primitive operations needed to implement the DAVID/SEED interface, and describes certain programming tools used. The remainder of the thesis deals with specifics of the implementation. Chapter 2 details implementation of the Schema conversion. Chapter 3 details the implementation of the automatic generation code used in translating queries of the database. Chapter 4 details the implementation of the automatic generation of code used on translating transactions on the database.