59 search results - page 5 / 12 » Rewriting Unions of General Conjunctive Queries Using Views |
SIS
2007
13 years 8 months ago
2007
Access control models for XML data can be classified in two major categories: node filtering and query rewriting systems. The first category includes approaches that use access ...
ICDT
2003
ACM
14 years 20 days ago
2003
ACM
All the languages for querying semistructured data and the web use as an integral part regular expressions. Based on practical observations, finding the paths that satisfy those r...
DBPL
2001
Springer
13 years 12 months ago
2001
Springer
Abstract. We are interested in the theoretical foundations of the optimization of conjunctive regular path queries (CRPQs). The basic problem here is deciding query containment bot...
EDBT
2008
ACM
14 years 7 months ago
2008
ACM
We address the problem of generating a mediated schema from a set of relational data source schemas and conjunctive queries that specify where those schemas overlap. Unlike past a...
VLDB
2001
ACM
14 years 7 months ago
2001
ACM
The problem of answering queries using views is to find efficient methods of answering a query using a set of previously materialized views over the database, rather than accessing...