On solving efficiently the view selection problem under bag and bag-set semantics

作者:

Highlights:

• Query subexpressions do not always suffice for finding an optimal solution.

• Lgviews and subexpression views suffice for solving the bag version of the problem.

• d-Lgviews and subexpression views suffice for solving the bag-set version of the problem.

• Path-viewsets can be used to solve the bag version of the problem for path-queries.

• We prove significant conditions that useful viewsets satisfy under bag-set semantics.

摘要

Highlights•Query subexpressions do not always suffice for finding an optimal solution.•Lgviews and subexpression views suffice for solving the bag version of the problem.•d-Lgviews and subexpression views suffice for solving the bag-set version of the problem.•Path-viewsets can be used to solve the bag version of the problem for path-queries.•We prove significant conditions that useful viewsets satisfy under bag-set semantics.

论文关键词:View selection,Query rewriting,Bag semantics,Bag-set semantics

论文评审过程:Received 29 August 2012, Revised 12 December 2013, Accepted 8 January 2014, Available online 18 January 2014.

论文官网地址:https://doi.org/10.1016/j.is.2014.01.002