Many applications in analytical domains often have the need to "connect the dots" i.e., query about the structure of data. In bioinformatics for example, it is typical t...
Abstract. Social Network (SN) data has become ubiquitous, demanding advanced and flexible means to represent, transform and query such data. In addition to the intrinsic challenge...
The goal of this paper is to give an overview of the basics of the theory of RDF databases. We provide a formal definition of RDF that includes the features that distinguish this m...
The XPath language incorporates powerful primitives for formulating queries containing nested subexpressions which are existentially or universally quantified. However, even the b...
Most of work on partial information in databases asks which operations of standard languages, like relational algebra, can still be performed correctly in the presence of nulls. In...