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ICDE
1999
IEEE
89views Database» more  ICDE 1999»
16 years 8 months ago
Relative Prefix Sums: An Efficient Approach for Querying Dynamic OLAP Data Cubes
Range sum queries on data cubes are a powerful tool for analysis. A range sum query applies an aggregation operation (e.g., SUM) over all selected cells in a data cube, where the ...
Steven Geffner, Divyakant Agrawal, Amr El Abbadi, ...
WWW
2004
ACM
16 years 7 months ago
Index structures and algorithms for querying distributed RDF repositories
A technical infrastructure for storing, querying and managing RDF data is a key element in the current semantic web development. Systems like Jena, Sesame or the ICS-FORTH RDF Sui...
Heiner Stuckenschmidt, Richard Vdovjak, Geert-Jan ...
SIGMOD
2004
ACM
142views Database» more  SIGMOD 2004»
16 years 7 months ago
Conditional Selectivity for Statistics on Query Expressions
Cardinality estimation during query optimization relies on simplifying assumptions that usually do not hold in practice. To diminish the impact of inaccurate estimates during opti...
Nicolas Bruno, Surajit Chaudhuri
SIGMOD
2004
ACM
127views Database» more  SIGMOD 2004»
16 years 7 months ago
Efficient Query Reformulation in Peer-Data Management Systems
Peer data management systems (PDMS) offer a flexible architecture for decentralized data sharing. In a PDMS, every peer is associated with a schema that represents the peer's...
Igor Tatarinov, Alon Y. Halevy
PODS
2005
ACM
131views Database» more  PODS 2005»
16 years 7 months ago
Buffering in query evaluation over XML streams
All known algorithms for evaluating advanced XPath queries (e.g., ones with predicates or with closure axes) on XML streams employ buffers to temporarily store fragments of the do...
Ziv Bar-Yossef, Marcus Fontoura, Vanja Josifovski