We present the architecture and a performance assessment of an extensible query optimizer written in Venus. Venus is a general-purpose active-database rule language embedded in C+...
Query optimizers normally compile queries into one optimal plan by assuming complete knowledge of all cost parameters such asselectivity and resourceavailability. The execution of...
Group nearest neighbor (GNN) queries are a relatively new type of operations in spatial database applications. Different from a traditional kNN query which specifies a single quer...
In this paper, we are concerned with the distributed monitoring of P2P systems. We introduce the P2P Monitor system and a new declarative language, namely P2PML, for specifying mo...
In this paper, we propose a versatile disambiguation approach which can be used to make explicit the meaning of structure based information such as XML schemas, XML document struc...