Querying Graph Databases

  • Sergio Flesca
  • Sergio Greco
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1777)


Graph data is an emerging model for representing a variety of database contexts ranging from object-oriented databases to hypertext data. Also many of the recursive queries that arise in relational databases are, in practice, graph traversals. In this paper we present a language for searching graph-like databases. The language permits us to express paths in a graph by means of extended regular expressions. The proposed extension is based on the introduction of constructs which permit us i) to de_ne a partial order on the paths used to search the graph and, consequently, on the answers of queries, and ii) to cut off, nondeterministically, tuples with low priority. We present an algebra for partially ordered relations and an algorithm for the computation of path queries. Finally, we present applications to hypertext databases such as the Web.


Regular Expression Regular Language Database Graph Local Link Path Query 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Sergio Flesca
    • 1
  • Sergio Greco
    • 1
  1. 1.DEISUniv. della CalabriaRendeItaly

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