We consider the problem of evaluating multiple overlapping queries defined on data streams, where each query is a conjunction of multiple filters and each filter may be shared acr...
We present HERMES, a prototype system based on a powerful query language for trajectory databases, which enables the support of aggregative Location-Based Services (LBS). The key ...
Nikos Pelekis, Elias Frentzos, Nikos Giatrakos, Ya...
The Boolean semantics of SQL queries cannot adequately capture the "fuzzy" preferences and "soft" criteria required in non-traditional data retrieval applicati...
Chengkai Li, Min Wang, Lipyeow Lim, Haixun Wang, K...
We propose an approach for the selective enforcement of access control restrictions in, possibly distributed, large data collections based on two basic concepts: i) flexible autho...
Sabrina De Capitani di Vimercati, Sara Foresti, Su...
Due to their numerous benefits, relational systems play a major role in storing XML documents. XML also benefits relational systems by providing a means to publish legacy relatio...