All known algorithms for evaluating advanced XPath queries (e.g., ones with predicates or with closure axes) on XML streams employ buffers to temporarily store fragments of the do...
We consider here the exchange of Active XML (AXML) data, i.e., XML documents where some of the data is given explicitly while other parts are given only intensionally as calls to ...
We consider query optimization techniques for data intensive P2P applications. We show how to adapt an old technique from deductive databases, namely Query-Sub-Query (QSQ), to a s...
Some promising recent schemes for XML access control employ encryption for implementing security policies on published data, avoiding data duplication. In this paper we study one ...
Continuous queries in a Data Stream Management System (DSMS) rely on time as a basis for windows on streams and for defining a consistent semantics for multiple streams and updata...
We study the problem of answering queries over sources with limited access patterns. Given a first-order query Q, the problem is to decide whether there is an equivalent query whi...