ESQL : an extended SQL with object and deductive capabilities

Projet RODINESQL is an SQL upward-compatible database language that integrates in a uniform and clean way the essential concepts of relational, object-oriented and deductive databases. ESQL is intended for traditional data processing applications as well as more complex applications such as large expert systems. Therefore, ESQL's salient features are : a rich and extendible type system based on abstract data types (ADTs) implemented in various programming languages ; complex objects with object sharing by combining generic ADTs and object identity ; the capability of querying and updating relations containing simple or complex objects using SQL-compatible syntax and semantics ; and a Datalog-like deductive capability provided as an extension of the SQL view mechanism. ESQL's functional semantics enables uniform manipulation of ESQL data and should facilitate the implementation of the ESQL compiler

440 Proving Consistency of Database Transactions Written in Extended Pascal

Abstract-The purpose of this correspondence is to present an approach for verifying that explicitly stated integrity constraints are not violated by certain transactions. We utilize a relational model wherein constraints are given in a language based on fthe first-order predicate calculus. Transactions are written in terms of a Pascal-likehost language with embedded first-order predicate calculus capabilities allowing queries and updates. The technique for proving consistency of the transactions is based upon the Hoare axiomatic approach. We illustrate the method by means of an explicit example of a database updated by four types of transaction. A generalized transaction consistency verifier embodying this approach would considerably enhance transaction programming in a relational database management system. Index Terms-Consistency, correctness proof, integrity constraint, predicate calculus, relational database, transaction. I