Optimizing Queries with Universal Quantification in
Object-Oriented and Object-Relational Databases
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Authors:
- Jens Claußen
- Alfons Kemper
- Guido Moerkotte
- Klaus Peithner
Proc. of the 23st Intl. Conf. on Very Large Data Bases (VLDB),
Athens, Greece, August 1997, pages 286-295.
Abstract:
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We investigate the optimization and evaluation of
queries with universal quantification in the context of the
object-oriented and object-relational data models. The queries are
classified into 16 categories depending on the variables referenced
in the so-called range and quantifier predicates. For
the three most important classes we enumerate the known query
evaluation plans and devise some new ones. These alternative plans
are primarily based on anti-semijoin, division, generalized grouping
with count aggregation, and set difference. In order to evaluate the
quality of the many different evaluation plans a thorough
performance analysis on some sample database configurations was
carried out. The quantitative analysis reveals that---if
applicable---the anti-semijoin-based plans are superior to all the
other alternatives, even if we employ the most sophisticated
division algorithms. Furthermore, exploiting object-oriented
features, anti-semijoin plans can be derived even when this is not
possible in the relational context.
An extented version is available as
Technical Report MIP-9706, Universität Passau, March 1997
download complete text (postscript, 178k)
Last modified: Wed Nov 10 12:05:03 MET 1999