243 search results - page 3 / 49 » Selectivity Estimation for Boolean Queries |
ICDT
2007
ACM
15 years 3 months ago
2007
ACM
Abstract. We study containment of conjunctive queries that are evaluated over databases that may contain tuples with null values. We assume the semantics of SQL for single block qu...
103
Voted
EDBT
2006
ACM
15 years 9 months ago
2006
ACM
In this paper we present a novel approach for estimating the selectivity of XML twig queries. Such a technique is useful for approximate query answering as well as for determining...
SIGMOD
2001
ACM
15 years 9 months ago
2001
ACM
Estimating the result size of complex queries that involve selection on multiple attributes and the join of several relations is a difficult but fundamental task in database query...
ADC
2004
Springer
15 years 3 months ago
2004
Springer
Many spatio-temporal applications involve managing and querying moving objects. In such an environment, predictive spatio-temporal queries become an important query class to be pr...
SIGMOD
1994
ACM
15 years 1 months ago
1994
ACM
In this paper, we propose a novel approach for estimating the record selectivities of database queries. The real attribute value distribution is adaptively approximated by a curve...