华东师范大学学报(自然科学版)

• 计算机科学 • 上一篇    下一篇

两种新的非确定数据库上的Top-k查询

邱 鑫, 林 欣   

  1. 上海市多维度信息处理重点实验室 华东师范大学, 上海 200241
  • 收稿日期:2015-11-27 出版日期:2017-01-25 发布日期:2017-01-13
  • 通讯作者: 林 欣, 男, 副教授, 研究方向为新型数据处理. E-mail: xlin@cs.ecnu.edu.cn.
  • 基金资助:

    国家自然科学基金(61572193);
    上海张江国家自主创新示范区专项发展基金(201411-JA-B108-002);
    上海市科学技术委员会项目(14DZ2260800)

Two new Top-k queries in uncertain database

QIU Xin, LIN Xin   

  1. Shanghai Key Laboratory of Multidimensional Information Processing, East China Normal University, Shanghai 200241, China
  • Received:2015-11-27 Online:2017-01-25 Published:2017-01-13

摘要:

由于当前已有的在非确定数据库上的 Top-k 查询普遍基于元组层面, 使得应用受限. 为了让查询结果更符合直觉, 提出了两种新的非确定数据库上的基于 x-元组层面的 Top-k 查询及其执行算法. 这两种新的查询综合 x-元组中各元组的评分和置信度, 获得在返回结果中最具实际意义的位置. 查询的执行算法经过优化,执行效率明显改善.

关键词: 非确定数据库, Top-k 查询

Abstract:

Since the pre-existing Top-k queries in uncertain databases almost are based on tuple level rather than x-tuple level restricts its application. The paper proposes two new instance-level Top-k queries and executive algorithm in uncertain databases in order to get intuitive query results. These two new queries take both  rank and confidence of each x-tuple’s tuple, figuring out the most meaningful position in the returned results. After the optimization of the executive algorithm, its executive efficiency has been improved significantly.

Key words: uncertain database, Top-k query