127 search results - page 5 / 26 » Conjunctive Query Containment under Access Limitations |
DEXAW
1998
IEEE
14 years 2 months ago
1998
IEEE
Materialized views offer opportunities for significant performance gain in query evaluation by providing fast access to pre-computed data. The question of when and how to use a ma...
EDBT
2006
ACM
14 years 10 months ago
2006
ACM
Current methods for selectivity estimation fall into two broad categories, synopsis-based and sampling-based. Synopsis-based methods, such as histograms, incur minimal overhead at ...
ICDT
2012
ACM
12 years 5 days ago
2012
ACM
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...
ICDE
1997
IEEE
14 years 11 months ago
1997
IEEE
A mediator is a domain-speci c tool to support uniform access to multiple heterogeneous information sources and to abstract and combine data from different but related databases t...
ICDE
2008
IEEE
14 years 11 months ago
2008
IEEE
We study the problem of auditing a batch of SQL queries: Given a forbidden view of a database that should have been kept confidential, a batch of queries that were posed over this ...