Graph databases have received much attention as of late due to numerous applications in which data is naturally viewed as a graph; these include social networks, RDF and the Semantic Web, biological databases, and many others. There are many proposals ...

We study the satisfiability problem for XPath with data equality tests. XPath is a node selecting language for XML documents whose satisfiability problem is known to be undecidable, even for very simple fragments. However, we show that the ...

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 ...

We investigate the satisfiability problem for downward-XPath, the fragment of XPath that includes the child and descendant axes, and tests for (in)equality of attributes’ values. We prove that this problem is decidable, EXPTIME-complete. These bounds ...

Data trees provide a standard abstraction of XML documents with data values: they are trees whose nodes, in addition to the usual labels, can carry labels from an infinite alphabet (data). Therefore, one is interested in decidable formalisms for ...

Graph data models received much attention lately due to applications in social networks, semantic web, biological databases and other areas. Typical query languages for graph databases retrieve their topology, while actual data stored in them is usually ...

Data trees provide a standard abstraction of XML documents with data values: they are trees whose nodes, in addition to the usual labels, can carry labels from an infinite alphabet (data). Therefore, one is interested in decidable formalisms for ...

In this work we investigate the satisfiability problem for the logic XPath(↓*, ↓,=), that includes all downward axes as well as equality and inequality tests. We address this problem in the absence of DTDs and the sibling axis. We prove that this ...

The Table Lens, focus+context visualization for large data tables, allows users to see 100 times as many data values as a spreadsheet in the same screen space in a manner that enables an extremely immediate form of exploratory data analysis. In the ...

Abstract: In general, the services of a distributed system are provided by some cooperative protocol entities. The protocol entities must exchange some data values and synchronization messages in order to ensure the temporal ordering of the events which ...

We propose an automatic analysis and test case derivation method for LOTOS expressions with data values. We introduce the class of P-LOTOS expressions where the data types are restricted to Presburger arithmetic. That is, only the integer and Boolean ...

A number system that offers advantages in some situations over conventional floating point and sign/logarithmic number systems is described. Redundant logarithmic arithmetic, like conventional logarithmic arithmetic, relies on table lookups to make the ...