ADDS: A system for automatic database schema design based on the binary-relationship model

Abstract

This paper presents the system ADDS that has been developed to assist the database designer designing a database schema. A distinction is made between the stage of information structure analysis in which the information structure of the system is defined according to its user information needs, and the stage of database schema design in which the record types of the database and the relationships between them are defined. In the first stage a conceptual schema is obtained, represented as an information structure diagram (ISD), and in the later stage the ISD is used to derive the database schema in the form of a data structure diagram (DSD). ADDS automatically creates the database schema out of a conceptual schema which is expressed as an ISD of the binary-relationship data mode. The resulting schema consists of normalized record types, according to the relation model, along with hierarchical/set relationships between ‘owner’ and ‘member’ record types, as in the CODASYL/Network model. ADDS applies algorithms to convert the conceptual schema into the database schema. It is implemented on a micro-computer under MS-DOS using dBASE III.