Gambit: An interactive database design tool for data structures, integrity constraints and transactions

A comprehensive and successful database definition is achieved by combining various description tools and design techniques. Our extended relational data model assists the designer in outlining and describing data structures with consistency preserving update transactions. A conceptual schema developed using the interactive database design system Gambit embodies all semantic integrity constraints perceived in the real world. These constraints are formulated using the database programming language Modula/R which is based upon first order predicate calculus. In order to enforce the checking of all integrity constraints, transactions (defined by specifying the involved entity sets) are generated automatically and collected in so called data modules. These modules are the only interface to the database apart from read operations.