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ALT
2000
Springer
13 years 10 months ago
On the Hardness of Learning Acyclic Conjunctive Queries
A conjunctive query problem in relational database theory is a problem to determine whether or not a tuple belongs to the answer of a conjunctive query over a database. Here, a tup...
Kouichi Hirata
PODS
2010
ACM
205views Database» more  PODS 2010»
13 years 10 months ago
Positive higher-order queries
We investigate a higher-order query language that embeds operators of the positive relational algebra within the simply-typed λ-calculus. Our language allows one to succinctly de...
Michael Benedikt, Gabriele Puppis, Huy Vu
ECSQARU
2009
Springer
14 years 9 days ago
Realizing Default Logic over Description Logic Knowledge Bases
Abstract. We consider a realization of Reiter-style default logic on top of description logic knowledge bases (DL-KBs). To this end, we present elegant transformations from default...
Minh Dao-Tran, Thomas Eiter, Thomas Krennwallner
KRDB
2003
184views Database» more  KRDB 2003»
13 years 7 months ago
Some Practical Issues in Building a Hybrid Deductive Geographic Information System with a DL Component
We report about some preliminary issues from the DFG project “Description Logics and Spatial Reasoning” (“DLS”, DFG Grant NE 279/8-1), one of whose goals is to develop a p...
Michael Wessel
ICDT
2012
ACM
251views Database» more  ICDT 2012»
11 years 8 months ago
Computing universal models under guarded TGDs
A universal model of a database D and a set Σ of integrity constraints is a database that extends D, satisfies Σ, and is most general in the sense that it contains sound and co...
André Hernich