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» Datalog Queries of Set Constraint Databases
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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
PODS
2005
ACM
147views Database» more  PODS 2005»
14 years 7 months ago
Peer data exchange
Abstract. We present a semantics and answer set programs for relational peer data exchange systems. When a peer answers a query, it exchanges data with other peers in order to supp...
Ariel Fuxman, Phokion G. Kolaitis, Renée J....
ICDE
2010
IEEE
172views Database» more  ICDE 2010»
13 years 7 months ago
On the use of query-driven XML auto-indexing
— Autonomous index management in native XML DBMSs has to address XML’s flexibility and storage mapping features, which provide a rich set of indexing options. Change of worklo...
Karsten Schmidt 0002, Theo Härder
ICDT
2010
ACM
161views Database» more  ICDT 2010»
14 years 4 months ago
Composition with Target Constraints
It is known that the composition of schema mappings, each specified by source-to-target tgds (st-tgds), can be specified by a secondorder tgd (SO tgd). We consider the question of...
Marcelo Arenas, Ronald Fagin, Alan Nash
DAWAK
2001
Springer
13 years 12 months ago
Shared Index Scans for Data Warehouses
Tree based indexing structures like -trees, ·-trees, Bitmap indexes and Ê-trees have become essential for getting good performance when accessing vast datasets. However, most dat...
Yannis Kotidis, Yannis Sismanis, Nick Roussopoulos