ICDT
2010
ACM
13 years 6 months ago
2010
ACM
When a query is evaluated under bag semantics, each answer is returned as many times as it has derivations. Bag semantics has long been recognized as important, especially when ag...
PODS
2006
ACM
14 years 4 months ago
2006
ACM
Query containment is a fundamental algorithmic problem in database query processing and optimization. Under set semantics, the query-containment problem for conjunctive queries ha...
ICDE
2004
IEEE
14 years 6 months ago
2004
IEEE
We describe and evaluate a query minimization technique that applies to XQueries, which are nested, perform arbitrary joins, and freely mix bag and set semantics. These features c...