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ER
2005
Springer
136views Database» more  ER 2005»
14 years 1 months ago
A Semantic Approach to Query Rewriting for Integrated XML Data
Query rewriting is a fundamental task in query optimization and data integration. With the advent of the web, there has been renewed interest in data integration, where data is dis...
Xia Yang, Mong-Li Lee, Tok Wang Ling, Gillian Dobb...
VLDB
1989
ACM
114views Database» more  VLDB 1989»
13 years 11 months ago
Extending the Relational Algebra to Capture Complex Objects
An important direction in database research for non-standard applications (e.g. engineering or design applications) deals with adequate support for complex objects. Without doubt,...
Bernhard Mitschang
DOOD
1995
Springer
124views Database» more  DOOD 1995»
13 years 11 months ago
Querying Semistructured Heterogeneous Information
Abstract. Semistructured data has no absolute schema xed in advance and its structure may be irregular or incomplete. Such data commonly arises in sources that do not impose a rigi...
Dallan Quass, Anand Rajaraman, Yehoshua Sagiv, Jef...
PODS
2008
ACM
165views Database» more  PODS 2008»
14 years 7 months ago
Data exchange and schema mappings in open and closed worlds
In the study of data exchange one usually assumes an openworld semantics, making it possible to extend instances of target schemas. An alternative closed-world semantics only move...
Leonid Libkin, Cristina Sirangelo
ESWS
2008
Springer
13 years 9 months ago
Foundations of RDF Databases
The goal of this paper is to give an overview of the basics of the theory of RDF databases. We provide a formal definition of RDF that includes the features that distinguish this m...
Claudio Gutierrez