Sciweavers

PODS
2010
ACM
197views Database» more  PODS 2010»
14 years 19 days ago
When data dependencies over SQL tables meet the logics of paradox and S-3
We study functional and multivalued dependencies over SQL tables with NOT NULL constraints. Under a no-information interpretation of null values we develop tools for reasoning. We...
Sven Hartmann, Sebastian Link
PODS
2010
ACM
228views Database» more  PODS 2010»
14 years 2 months ago
Capturing missing tuples and missing values
Databases in real life are often neither entirely closed-world nor entirely open-world. Indeed, databases in an enterprise are typically partially closed, in which a part of the d...
Wenfei Fan, Floris Geerts
PODS
2010
ACM
223views Database» more  PODS 2010»
14 years 2 months ago
Characterizing schema mappings via data examples
Schema mappings are high-level specifications that describe the relationship between two database schemas; they are considered to be the essential building blocks in data exchange...
Bogdan Alexe, Phokion G. Kolaitis, Wang Chiew Tan
PODS
2010
ACM
193views Database» more  PODS 2010»
14 years 2 months ago
Performance guarantees for B-trees with different-sized atomic keys
Michael A. Bender, Haodong Hu, Bradley C. Kuszmaul
PODS
2010
ACM
159views Database» more  PODS 2010»
14 years 2 months ago
On probabilistic fixpoint and Markov chain query languages
We study highly expressive query languages such as datalog, fixpoint, and while-languages on probabilistic databases. We generalize these languages such that computation steps (e....
Daniel Deutch, Christoph Koch, Tova Milo
PODS
2010
ACM
249views Database» more  PODS 2010»
14 years 5 months ago
Semantic query optimization in the presence of types
Both semantic and type-based query optimization rely on the idea that queries often exhibit non-trivial rewritings if the state space of the database is restricted. Despite their ...
Michael Meier 0002, Michael Schmidt, Fang Wei, Geo...
PODS
2010
ACM
174views Database» more  PODS 2010»
14 years 5 months ago
Fast Manhattan sketches in data streams
Jelani Nelson, David P. Woodruff
PODS
2010
ACM
181views Database» more  PODS 2010»
14 years 5 months ago
Schema design for XML repositories: complexity and tractability
Abiteboul et al. initiated the systematic study of distributed XML documents consisting of several logical parts, possibly located on different machines. The physical distributio...
Wim Martens, Matthias Niewerth, Thomas Schwentick
PODS
2010
ACM
250views Database» more  PODS 2010»
14 years 5 months ago
From information to knowledge: harvesting entities and relationships from web sources
There are major trends to advance the functionality of search engines to a more expressive semantic level. This is enabled by the advent of knowledge-sharing communities such as W...
Gerhard Weikum, Martin Theobald