The problem of SPARQL query containment is defined as determining if the result of one query is included in the result of another for any RDF graph. Query containment is important...
A data stream management system executes a large number of continuous queries in parallel. As stream characteristics and query workload change over time, the plan initially install...
Relational index structures, as for instance the Relational Interval Tree or the Linear Quadtree, support efficient processing of queries on top of existing object-relational datab...
Hans-Peter Kriegel, Peter Kunath, Martin Pfeifle, ...
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...
Virtually every commercial query optimizer chooses the best plan for a query using a cost model that relies heavily on accurate cardinality estimation. Cardinality estimation erro...
Volker Markl, Vijayshankar Raman, David E. Simmen,...