Research into Declarative, Object-Oriented Languages for Programming Data and Knowledge

用于编程数据和知识的声明性面向对象语言的研究

• 批准号: 9404629
• 负责人: Michael Kifer
• 金额: $ 18.8万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-10-01 至 1998-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9404629&HistoricalAwards=false
• 关键词: Research; into; Declarative; Object; Oriented

Relational query languages, such as SQL, were the early success stories of declarative programming. However, as new applications areas have developed, relational systems have been found wanting. Their limitations--both structural and language related--have led databases and deductive databases. Object-oriented databases (abbr., O-O) are effective when the structure of the data is well- known and the data access paths and retrieval methods can be determined at system development time. Deductive DBMS, based on logic, are appropriate in less well-defined situations; situations where one does not know before-hand all the queries that will be asked. Flexibility is extremely important for modern DBMS, especially when the user lacks detailed knowledge about the structure of the application domain. For this reason, logic-base languages have traditionally been used whenever intelligent processing of data was required. On the other hand, flat data structures inherent in such languages are ill-suited for many scientific applications, CAD/CAM design, modeling agile manufacturing processing, etc., where data has complex and known internal structure.

关系查询语言，如SQL，是声明式编程的早期成功案例。 然而，随着新的应用领域的发展，关系系统已被发现需要。 它们的局限性--结构上和语言上的--导致了数据库和演绎数据库的出现。 面向对象的数据库（简称，当数据的结构是众所周知的，并且数据访问路径和检索方法可以在系统开发时确定时，O-O）是有效的。 基于逻辑的演绎DBMS适用于定义不太明确的情况;在这种情况下，人们事先不知道将被询问的所有查询。 灵活性对于现代DBMS是极其重要的，尤其是当用户缺乏关于应用程序域结构的详细知识时。 出于这个原因，逻辑基语言传统上被用于需要智能处理数据的任何时候。 另一方面，这种语言中固有的平面数据结构不适合许多科学应用、CAD/CAM设计、建模敏捷制造处理等，其中数据具有复杂且已知的内部结构。