RIA: Towards A Generic Visual Query Language for Object- Oriented Systems

RIA：面向对象数据库的具有正式基础的通用可视化查询语言。这是一个持续三年的奖项的第一年资助。面向对象数据库已被公认为对高级非传统应用（如设计、计划、调度和地理应用）非常有用。最近开发了许多面向对象的数据模型。为了方便在这些完全不同的模型中进行查询，已经提出了许多可视化查询语言。该项目确定了面向对象应用程序中可视化查询所需的基本结构，并使用它们来设计和实现通用的可视化查询语言。这种语言优雅地从关系模型和嵌套模型扩展到完全不同的面向对象模型（可扩展性）。它使用尽可能少的基本语言结构，同时又具有足够的通用性，可以编码各种面向对象语言的专门查询特性（核心语言结构很少，但功能强大）。此外，这种编码是用户友好的。通用语言有很强的理论基础：(1)实现形式语义，适当考虑安全性、否定性等，有衡量表达性和复杂性的形式基础；(2)证明构造的最小性，并展示它们如何模拟其他有用的查询构造，等等。这种通用语言将为各种面向对象模型和应用程序的用户提供统一的前端，并且如果在客户机-服务器环境中作为服务器（类似于sql服务器）开发，将发挥重要作用。

RIA: Towards a Generic Visual Query Language with Formal Basis for Object-Oriented Databases This is the first year funding of a three-year continuing award. Object-oriented databases have been recognized as very useful for advanced non-traditional applications such as design, planning, scheduling and geographic applications. Recently a number of object-oriented data models have been developed. To facilitate easy querying in these disparate models, a number of visual query languages have been proposed. This project identifies the basic constructs required for visual querying in object-oriented applications, and uses them to design and implement a generic visual query language. This language extends gracefully from relational and nested models to disparate object-oriented models (extendibility). It uses as few basic language constructs as necessary, while at the same time is versatile enough to encode specialized query-features of diverse object-oriented languages (few but powerful core language constructs). Furthermore, such encodings are user-friendly. The generic language has strong theoretical foundations: (1) enabling formal semantics, with proper consideration for safety, negation, etc., and a formal basis for measuring expressivity and complexity; and (2) proving minimality of the constructs and showing how they simulate other useful query-constructs, etc. Such a generic language will provide a uniform front-end to users of diverse object-oriented models and applications, and will play an important role if developed as a server (analogous to SQL-servers) in a client- server environment.