Typed Programming Languages for Databases

数据库的类型化编程语言

• 批准号: 9004137
• 负责人: O. Peter Buneman
• 金额: $ 14.5万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-09-15 至 1993-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9004137&HistoricalAwards=false
• 关键词: Typed; Programming; Languages; Databases

While considerable progress has been made in the past three years on the static typechecking of object-oriented languages, object- oriented databases pose additional problems. In particular we need to clarify the relationship between type and extent. The relationship EMPLOYEE PERSON as a relationship between classes or types says something about the inheritance of methods, while in a database context it also means set inclusion. There is an apparent contradiction: how can a set of one type be a subset of a set of some other type? The use of "partially dynamic" types is investigated in order to resolve this issue, which will allow us to deal with heterogeneous collections in a statically typed system. The rules for type checking for heterogeneous collections appear to be closely related to those already developed for manipulating relational databases. If this is the case, then type inference should also be possible. Research plan includes development of a prototype language that demonstrates the feasibility of these ideas.

虽然过去三年在面向对象语言的静态类型检查方面取得了相当大的进展，但面向对象数据库也带来了其他问题。 特别是我们需要澄清类型和范围之间的关系。 EMPLOYEE PERSON 关系作为类或类型之间的关系说明了方法的继承，而在数据库上下文中，它也意味着集合包含。 有一个明显的矛盾：一种类型的集合怎么可能是另一种类型的集合的子集？ 为了解决这个问题，我们研究了“部分动态”类型的使用，这将使我们能够在静态类型系统中处理异构集合。 异构集合的类型检查规则似乎与已经开发的用于操作关系数据库的规则密切相关。 如果是这种情况，那么类型推断也应该是可能的。研究计划包括开发一种原型语言来证明这些想法的可行性。