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» Optimizing complex queries with multiple relation instances
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ESWS
2011
Springer
12 years 11 months ago
Optimizing Query Shortcuts in RDF Databases
The emergence of the Semantic Web has led to the creation of large semantic knowledge bases, often in the form of RDF databases. Improving the performance of RDF databases necessit...
Vicky Dritsou, Panos Constantopoulos, Antonios Del...
ICDE
2003
IEEE
148views Database» more  ICDE 2003»
14 years 9 months ago
Efficient Computation of Subqueries in Complex OLAP
Expressing complex OLAP queries using group-by, aggregation, and joins can be extremely difficult. As a result of this, many alternate ways of expressing such queries have been de...
Michael H. Böhlen, Michael O. Akinde
MDM
2009
Springer
123views Communications» more  MDM 2009»
14 years 2 months ago
Operator Placement for Snapshot Multi-predicate Queries in Wireless Sensor Networks
— This work aims at minimize the cost of answering snapshot multi-predicate queries in high-communication-cost networks. High-communication-cost (HCC) networks is a family of net...
Georgios Chatzimilioudis, Huseyin Hakkoymaz, Nikos...
ICDT
1995
ACM
79views Database» more  ICDT 1995»
13 years 11 months ago
Optimization Using Tuple Subsumption
A tuple t1 of relation R subsumes tuple t2 of R, with respect to a query Q if for every database, tuple t1 derives all, and possibly more, answers to query Q than derived by tuple ...
Venky Harinarayan, Ashish Gupta
VLDB
1992
ACM
151views Database» more  VLDB 1992»
13 years 11 months ago
A Uniform Approach to Processing Temporal Queries
Research in temporal databases has mainly focused on defining temporal data models by extending existing models, and developing access structures for temporal data. Little has bee...
Umeshwar Dayal, Gene T. J. Wuu