Two-Variable Logic on Data Trees and XML Reasoning

Mikolaj Bojanczyk (1) , Claire David (2) , Anca Muscholl (2) , Thomas Schwentick (3) , Luc Segoufin (4)

1 Institute of Informatics [Warsaw]
2 LIAFA - Laboratoire d'informatique Algorithmique : Fondements et Applications
3 FBI - Fachbereich Informatik
4 GEMO - Integration of data and knowledge distributed over the web

Motivated by reasoning tasks in the context of XML languages, the satisfiability problem of logics on data trees is investigated. The nodes of a data tree have a label from a finite set and a data value from a possibly infinite set. It is shown that satisfiability for two-variable first-order logic is decidable if the tree structure can be accessed only through the child and the next sibling predicates and the access to data values is restricted to equality tests. From this main result decidability of satisfiability and containment for a data-aware fragment of XPath and of the implication problem for unary key and inclusion constraints is concluded.

Domaines: Informatique et langage [cs.CL]; Base de données [cs.DB]

Mikolaj Bojanczyk, Claire David, Anca Muscholl, Thomas Schwentick, Luc Segoufin. Two-Variable Logic on Data Trees and XML Reasoning. twenty-fifth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database system, 2006, Chicago, United States. pp.10-19, ⟨10.1145/1142351.1142354⟩. ⟨hal-00151833⟩