Data streams are modeled as infinite or finite sequences of data elements coming from an arbitrary but fixed universe. The universe can have various built-in functions and predi...
This paper presents an application of a DL reasoner to the optimization of an object-relational query language. Queries containing aggregate functions are difficult to optimize be...
Many online or local data sources provide powerful querying mechanisms but limited ranking capabilities. For instance, PubMed allows users to submit highly expressive Boolean keywo...
Panagiotis G. Ipeirotis, Vagelis Hristidis, Yuheng...
This paper introduces a new approach of approximating the selectivity of multimedia range queries. Estimating the selectivity of a range query is a pre-requisite to optimize a mul...
This paper is mainly concerned with the extension of database management systems querying capabilities, so that users may address queries involving preferences and get discriminate...