Making smalltalk a database system 论文

摘要

To overcome limitations in the modeling power of existing database systems and provide a better tool for database application programming, Servio Logic Corporation is developing a computer system to support a set-theoretic data model in an object-oriented programming environment We recount the problems with existing models and database systems We then show how features of Smalltalk, such such as operational semantics, its type hierarchy, entity identity and the merging of programming and data language, solve many of those problems Nest we consider what Smalltalk lacks as a database system secondary storage management, a declarative semantics, concurrency, past states To address these shortcomings, we needed a formal data model We introduce the GemStone data model, and show how it helps to define path expressions, a declarative semantics and object history in the OPAL language We summarize similar approaches, and give a brief overview of the GemStone system implementation