Semantics and Complexity of SPARQL [chapter]

Jorge Pérez, Marcelo Arenas, Claudio Gutierrez
2006 Lecture Notes in Computer Science  
SPARQL is the W3C candidate recommendation query language for RDF. In this paper we address systematically the formal study of SPARQL, concentrating in its graph pattern facility. We consider for this study a fragment without literals and a simple version of filters which encompasses all the main issues yet is simple to formalize. We provide a compositional semantics, prove there are normal forms, prove complexity bounds, among others that the evaluation of SPARQL patterns is PSPACE-complete,
more » ... mpare our semantics to an alternative operational semantics, give simple and natural conditions when both semantics coincide and discuss optimizations procedures.
doi:10.1007/11926078_3 fatcat:w2lx2pkw6fhu3mcxwyedlkscda