A graphical query language supporting recursion
SIGMOD '87 Proceedings of the 1987 ACM SIGMOD international conference on Management of data
GraphLog: a visual formalism for real life recursion
PODS '90 Proceedings of the ninth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Regular path queries with constraints
Journal of Computer and System Sciences
Dynamic Logic
ACM SIGMOD Record
Elements Of Finite Model Theory (Texts in Theoretical Computer Science. An Eatcs Series)
Elements Of Finite Model Theory (Texts in Theoretical Computer Science. An Eatcs Series)
Efficient algorithms for processing XPath queries
ACM Transactions on Database Systems (TODS)
ACM Transactions on Database Systems (TODS) - Special Issue: SIGMOD/PODS 2004
The expressivity of XPath with transitive closure
Proceedings of the twenty-fifth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Static analysis of XML processing with data values
ACM SIGMOD Record
Survey of graph database models
ACM Computing Surveys (CSUR)
Navigational XPath: calculus and algebra
ACM SIGMOD Record
SoQL: A Language for Querying and Creating Data in Social Networks
ICDE '09 Proceedings of the 2009 IEEE International Conference on Data Engineering
Representing, Querying and Transforming Social Networks with RDF/SPARQL
ESWC 2009 Heraklion Proceedings of the 6th European Semantic Web Conference on The Semantic Web: Research and Applications
Semantics and complexity of SPARQL
ACM Transactions on Database Systems (TODS)
The complexity of query containment in expressive fragments of XPath 2.0
Journal of the ACM (JACM)
An Automata-Theoretic Approach to Regular XPath
DBPL '09 Proceedings of the 12th International Symposium on Database Programming Languages
Expressive languages for path queries over graph-structured data
Proceedings of the twenty-ninth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
nSPARQL: A navigational language for RDF
Web Semantics: Science, Services and Agents on the World Wide Web
An Extension of Data Automata that Captures XPath
LICS '10 Proceedings of the 2010 25th Annual IEEE Symposium on Logic in Computer Science
Graph pattern matching: from intractable to polynomial time
Proceedings of the VLDB Endowment
Relative expressive power of navigational querying on graphs
Proceedings of the 14th International Conference on Database Theory
Foundations of Semantic Web databases
Journal of Computer and System Sciences
XPath evaluation in linear time
Journal of the ACM (JACM)
The complexity of evaluating path expressions in SPARQL
PODS '12 Proceedings of the 31st symposium on Principles of Database Systems
FoIKS'12 Proceedings of the 7th international conference on Foundations of Information and Knowledge Systems
Graph pattern matching revised for social network analysis
Proceedings of the 15th International Conference on Database Theory
Regular path queries on graphs with data
Proceedings of the 15th International Conference on Database Theory
Graph Logics with Rational Relations and the Generalized Intersection Problem
LICS '12 Proceedings of the 2012 27th Annual IEEE/ACM Symposium on Logic in Computer Science
Semantic acyclicity on graph databases
Proceedings of the 32nd symposium on Principles of database systems
Proceedings of the 32nd symposium on Principles of database systems
Trial for RDF: adapting graph query languages for RDF data
Proceedings of the 32nd symposium on Principles of database systems
The complexity of regular expressions and property paths in SPARQL
ACM Transactions on Database Systems (TODS) - Invited papers issue
Hi-index | 0.00 |
XPath plays a prominent role as an XML navigational language due to several factors, including its ability to express queries of interest, its close connection to yardstick database query languages (e.g., first-order logic), and the low complexity of query evaluation for many fragments. Another common database model---graph databases---also requires a heavy use of navigation in queries; yet it largely adopts a different approach to querying, relying on reachability patterns expressed with regular constraints. Our goal here is to investigate the behavior and applicability of XPath-like languages for querying graph databases, concentrating on their expressiveness and complexity of query evaluation. We are particularly interested in a model of graph data that combines navigation through graphs with querying data held in the nodes, such as, for example, in a social network scenario. As navigational languages, we use analogs of core and regular XPath and augment them with various tests on data values. We relate these languages to first-order logic, its transitive closure extensions, and finite-variable fragments thereof, proving several capture results. In addition, we describe their relative expressive power. We then show that they behave very well computationally: they have a low-degree polynomial combined complexity, which becomes linear for several fragments. Furthermore, we introduce new types of tests for XPath languages that let them capture first-order logic with data comparisons and prove that the low complexity bounds continue to apply to such extended languages. Therefore, XPath-like languages seem to be very well-suited to query graphs.