5 Dec 2003
Efficient Processing of Joins on Set-valued Attributes
Speaker: Dr. Nikos Mamoulis
Abstract
Object-oriented and object-relational DBMS support set-valued attributes,
which are a natural and concise way to model complex information. However,
there has been limited research to-date on the evaluation of query
operators that apply on sets. In this talk, methods that join two
relations on their set-valued attributes will be presented. Various join
types are considered, namely the set containment, set equality, and set
overlap joins. We show that the inverted file, a powerful index for
selection queries, can also facilitate the efficient evaluation of most
join predicates. We propose join algorithms that utilize inverted files
and compare them with signature-based methods for several set-comparison
predicates.
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