Optimization of join queries based on average selectivities is suboptimal in highly correlated databases. In such databases, relations are naturally divided into partitions, each ...
Kostas Tzoumas, Amol Deshpande, Christian S. Jense...
We present the systematic design and development of a distributed query scheduling service DQS in the context of DIOM, a distributed and interoperable query mediation system 26 ...
Query optimization in RDF Stores is a challenging problem as SPARQL queries typically contain many more joins than equivalent relational plans, and hence lead to a large join orde...
With the wide adoption of XML as a standard data representation and exchange format, querying XML documents becomes increasingly important. However, relational database systems co...
Popular XML languages, like XPath, use “treepattern” queries to select nodes based on their structural characteristics. While many processing methods have already been propose...