119
click to vote
AMW
15 years 1 months ago
2009 
We investigate the space requirements for summaries needed for maintaining exact answers to aggregate queries over histories of relational databases. We show that, in general, a su...
102
Voted
AMW
15 years 1 months ago
2009 
Abstract. A Data Warehouse (DW) is a data repository that organizes and physically integrates data from multiple sources under special kinds of schemas. A DW is composed by a set o...
139
Voted
AMW
15 years 1 months ago
2009 
This paper presents an abstract data model for visualizing RDF data based on the notion of nested graphs. Our study gives theoretical results that shows directions to enhance the r...
105
click to vote
AMW
15 years 1 months ago
2009 
Abstract. Rewriting of conjunctive queries using views has many applications in database and data integration. We investigate ways to improve performance of rewriting and propose a...
108
Voted
AMW
15 years 1 months ago
2009
Abstract. Peer data sharing systems use either schema-level or data-level mappings to resolve schema as well as data heterogeneity among data sources (peers). Schema-level mappings...
|
Knowledge Management