115 search results - page 6 / 23 » Predicate Migration: Optimizing Queries with Expensive Predi... |
BTW
2009
Springer
13 years 12 months ago
2009
Springer
: Cost-based optimizers in relational databases make use of data statistics to estimate intermediate result cardinalities. Those cardinalities are needed to estimate access plan co...
IS
2002
13 years 7 months ago
2002
In this paper, we explore the possibility of transforming queries with minimum and maximum predicates into equivalent queries that can be computed more efficiently. The main contr...
IJCAI
2003
13 years 8 months ago
2003
In data-integration systems, information sources often have various constraints such as “all houses stored at a source have a unique address.” These constraints are very usefu...
ICDE
2007
IEEE
14 years 8 months ago
2007
IEEE
Optimizing nested queries is an intricate problem. It becomes even harder if in a nested query the linking predicate or the correlation predicate occurs disjunctively. We present ...
PODS
2004
ACM
14 years 7 months ago
2004
ACM
The problem of deciding query containment has important applications in classical query optimization and heterogeneous database systems. Query containment is undecidable for unres...