Adding regular expressions to graph reachability and pattern queries

12 years 8 months ago

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—It is increasingly common to ﬁnd graphs in which edges bear different types, indicating a variety of relationships. For such graphs we propose a class of reachability queries and a class of graph patterns, in which an edge is speciﬁed with a regular expression of a certain form, expressing the connectivity in a data graph via edges of various types. In addition, we deﬁne graph pattern matching based on a revised notion of graph simulation. On graphs in emerging applications such as social networks, we show that these queries are capable of ﬁnding more sensible information than their traditional counterparts. Better still, their increased expressive power does not come with extra complexity. Indeed, (1) we investigate their containment and minimization problems, and show that these fundamental problems are in quadratic time for reachability queries and are in cubic time for pattern queries. (2) We develop an algorithm for answering reachability queries, in quadratic time as f...

Wenfei Fan, Jianzhong Li, Shuai Ma, Nan Tang, Ying

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