Object-oriented technology is an emerging information technology. Object-oriented database technology represents a breakthrough from the dominant relational model. Lacking the similar popularity and acceptance of SQL. object-oriented database management systems, however, are going through a difficult period of standardization. Due the complexity of object-oriented technology and the sophistication of distributed (Internet) computing, object database systems need an efficient and effective way to tackle the issue of heterogeneity and incompatibility. In this paper, we propose a syn tax-based gateway model to bridge two key object standards of SQL3 and ODMG. The gateway model is methodological and systematic. The basic belief is that a real representation of the real world has to be discovered to resolve the middleware issue. In this method. we employ a set of general and generic components and constructs that compose a real world object system. We use the set to compare and contrast the composition of SQL3 and ODMG. We devise a limited set of conversion rules to convert the compositions one at a time. A transformation model is built. This approach is traceable and reversible because it is based on analysis/design constructs. We have implemented the gateway model. The prototype is composed of an analyzing module, lexical scanner, and grammar parser.
