98 search results - page 2 / 20 » Query rewriting and answering under constraints in data inte... |
SIGMOD
2004
ACM
14 years 4 months ago
2004
ACM
We study the problem of answering queries through a target schema, given a set of mappings between one or more source schemas and this target schema, and given that the data is at...
AMW
2010
13 years 6 months ago
2010
We address the problem of answering conjunctive queries over knowledge bases, specified by sets of first-order sentences called tuple-generating dependencies (TGDs). This problem i...
17
Voted
PVLDB
2010
13 years 2 months ago
2010
Supporting legacy applications when the database schema evolves represents a long-standing challenge of practical and theoretical importance. Recent work has produced algorithms a...
SIGMOD
2005
ACM
14 years 4 months ago
2005
ACM
Although integrity constraints have long been used to maintain data consistency, there are situations in which they may not be enforced or satisfied. In this paper, we present Con...
PODS
2000
ACM
13 years 9 months ago
2000
ACM
The problem of query containment is fundamental to many aspects of database systems, including query optimization, determining independence of queries from updates, and rewriting ...