Temporally Enhanced Database Design
Temporally Enhanced Database Design
复制标题
临时增强数据库设计
DOI：
10.7551/mitpress/1131.003.0013
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
R. Snodgrass
中科院分区：
文献类型：
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作者：
Christian S. Jensen;R. Snodgrass
适当的数据库模式的设计对于有效使用数据库技术和构建利用该技术的有效信息系统至关重要。数据库模式的时间方面通常特别复杂，因此设计起来很困难且容易出错。本章重点讨论数据库模式的时间方面。它的贡献是双重的。首先，提出了一组全面的概念来捕获模式的时间方面。其次，探讨了这些概念在数据库设计中的使用。具体来说，本章为（时态）关系数据库的设计提供了新的指南。本章首先概括了应用于时态数据库的传统函数依赖关系，从而产生了时态键和范式。时间模式标识属性值何时更改以及更改何时记录在数据库中。生命周期描述了属性何时具有值。属性的时间支持和精度指示与属性相关的时间方面以及要以什么时间粒度来记录这些方面。推导函数描述了如何根据存储的值计算属性在其生命周期内所有时间的值。探讨了这些概念对数据库设计的影响。
The design of appropriate database schemas is critical to the effective use of database technology and the construction of effective information systems that exploit this technology. The temporal aspects of database schemas are often particularly complex and thus difficult and error-prone to design. This chapter focuses on the temporal aspects of database schemas. Its contributions are twofold. First, a comprehensive set of concepts are presented that capture temporal aspects of schemas. Second, the use of these concepts for database design is explored. Specifically, the chapter provides new guidelines for the design of (temporal) relational databases. The chapter first generalizes conventional functional dependencies to apply to temporal databases, leading to temporal keys and normal forms. Time patterns identify when attributes change values and when the changes are recorded in the database. Lifespans describe when attributes have values. The temporal support and precision of attributes indicate the temporal aspects that are relevant for the attributes and with what temporal granularity the aspects are to be recorded. And derivation functions describe how the values of an attribute for all times within its lifespan are computed from stored values. The implications of these concepts for database design are explored.