计算机工程与应用 ›› 2006, Vol. 42 ›› Issue (28): 5-.

• 博士论坛 • 上一篇    下一篇

全序时态模块模式的TO_TBCNF分解问题研究

万静,郝忠孝   

  1. 哈尔滨理工大学
  • 收稿日期:2006-07-07 修回日期:1900-01-01 出版日期:2006-10-01 发布日期:2006-10-01
  • 通讯作者: 万静 wanj wanj

Research on TO_TBCNF Decomposition with Total Order Temporal Module Scheme

,   

  1. 哈尔滨理工大学
  • Received:2006-07-07 Revised:1900-01-01 Online:2006-10-01 Published:2006-10-01

摘要: 时间粒度是所有时态数据所拥有的共同特点。在许多时态数据库应用中,都涉及多时间粒度约束,但是,具有多时间粒度的时态数据库的设计相当复杂,难以实现。而现实世界中的许多应用涉及到的时态类型集都能满足全序关系,由于具有全序时态类型集的全序时态模块模式有着良好的特性,文章提出了全序时态模块模式、时刻关系模式、全序时态模块投影和全序时态BC范式(TO_TBCNF)等概念,并给出了全序时态BC范式的分解算法,对其正确性、可终止性进行了证明,并对时间复杂度进行了分析。

Abstract: Temporal granularity is a feature common to all temporal data. Constraints involving multiple time granularities exist in many temporal database applications. However, design of temporal database with multiple time granularities is fairly complicated, even hard to implement. Temporal type sets involved in many real world applications can constitute one total order of types, and total order temporal module schemes with total order temporal type sets have fine properties. This paper gives the concepts of total order temporal module scheme, tickwise relation scheme, total order temporal module projection, total order temporal BCNF etc. The total order temporal BCNF decomposition algorithm, the proof for its correction and termination and the time complexity analysis are also given in this paper.