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» Exploiting statistics on query expressions for optimization
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CADE
2012
Springer
11 years 10 months ago
SPARQL Query Containment under RDFS Entailment Regime
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...
Melisachew Wudage Chekol, Jérôme Euze...
EDBTW
2006
Springer
13 years 11 months ago
Dynamic Plan Migration for Snapshot-Equivalent Continuous Queries in Data Stream Systems
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...
Jürgen Krämer, Yin Yang, Michael Cammert...
DASFAA
2004
IEEE
169views Database» more  DASFAA 2004»
13 years 11 months ago
Statistic Driven Acceleration of Object-Relational Space-Partitioning Index Structures
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, ...
EDBT
2012
ACM
247views Database» more  EDBT 2012»
11 years 10 months ago
Heuristics-based query optimisation for SPARQL
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...
Petros Tsialiamanis, Lefteris Sidirourgos, Irini F...
SIGMOD
2004
ACM
147views Database» more  SIGMOD 2004»
14 years 7 months ago
Robust Query Processing through Progressive Optimization
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,...