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Single-view determinacy and rewriting completeness for a fragment of XPath queries

一类 XPath 查询语句的视图确定性和重写完全性问题

摘要

创新点

研究一类含有通配符 (*)、 递归 (//)和分支 ([]) 操作的 XPath 查询语句的视图确定性和重写完全性问题。 证明出该类 XPath 语句的视图确定性问题是 coNP 难的, 并且该类语句是重写不完全的。 进而从语义和语法两个角度给出视图 V 确定查询 Q 的一系列必要条件, 以及一个判定视图确定性问题的非完全算法。 证明出对于一类特殊的 XPath 子类, 即只含有通配符和分支操作的 XPath 子类, 视图确定性问题可以在多项式时间内判定。 同时指出该子类的重写完全语言, 并给出一个从视图中计算查询结果的有效方法。

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Author information

Correspondence to Shuai Ma.

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The authors declare that they have no conflict of interest.

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Zheng, L., Ma, S., Luo, X. et al. Single-view determinacy and rewriting completeness for a fragment of XPath queries. Sci. China Inf. Sci. 59, 99102 (2016). https://doi.org/10.1007/s11432-016-5603-z

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关键词

  • XPath
  • 视图
  • 查询重写
  • 确定性
  • 复杂度