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SPIRE
2009
Springer
16 years 13 days ago
A Last-Resort Semantic Cache for Web Queries
We propose a method to evaluate queries using a last-resort semantic cache in a distributed Web search engine. The cache stores a group of frequent queries and for each of these qu...
Flavio Ferrarotti, Mauricio Marín, Marcelo ...
SIGMOD
1999
ACM
181views Database» more  SIGMOD 1999»
15 years 10 months ago
Approximate Computation of Multidimensional Aggregates of Sparse Data Using Wavelets
Computing multidimensional aggregates in high dimensions is a performance bottleneck for many OLAP applications. Obtaining the exact answer to an aggregation query can be prohibit...
Jeffrey Scott Vitter, Min Wang
MFCS
2009
Springer
16 years 13 days ago
Query Automata for Nested Words
We study visibly pushdown automata (VPA) models for expressing and evaluating queries, expressed using MSO formulas, on words with a nesting structure (like XML documents). We deļ...
P. Madhusudan, Mahesh Viswanathan
WEBDB
2009
Springer
112views Database» more  WEBDB 2009»
16 years 15 days ago
Querying DAG-shaped Execution Traces Through Views
The question whether a given set of views, defined by queries, can be used to answer another query, arises in several contexts such as query optimization, data integration and se...
Maya Ben-Ari, Tova Milo, Elad Verbin
VLDB
2001
ACM
144views Database» more  VLDB 2001»
16 years 6 months ago
Approximate query processing using wavelets
Approximate query processing has emerged as a costeffective approach for dealing with the huge data volumes and stringent response-time requirements of today's decision-suppo...
Kaushik Chakrabarti, Minos N. Garofalakis, Rajeev ...