Aufgrund von Vorbereitungen auf eine neue Version von KOPS, können kommenden Montag und Dienstag keine Publikationen eingereicht werden. (Due to preparations for a new version of KOPS, no publications can be submitted next Monday and Tuesday.)
Type of Publication: | Contribution to a conference collection |
URI (citable link): | http://nbn-resolving.de/urn:nbn:de:bsz:352-opus-15085 |
Author: | Grust, Torsten; Kröger, Joachim; Gluche, Dieter; Heuer, Andreas; Scholl, Marc H. |
Year of publication: | 1997 |
Published in: | Proceedings of the 15. British National Conference on Databases |
Summary: |
With the substantial change of declarative query languages
from plain SQL to the so-called "object SQLs", in particular OQL, there has surprisingly been not much change in the way problems of query representation and optimization for such languages are tackled. We identify some of the difficulties pure algebraic approaches experience when facing object models and the operations defined for them. Calculus-style formalisms suite this challenge better, but are said not to be efficiently implementable in the database context. This paper proposes a hybrid query representation and optimization approach, combining the strengths of a many-sorted query algebra and the monoid comprehension calculus. We show that efficient execution plans beyond nested-loop processing can be derived in such a framework. The translation process accounts for queries manipulating bulk-typed values by employing various join methods of the database engine, as well as queries that use aggregation, construction of arbitrary values, and arithmetics. |
Subject (DDC): | 004 Computer Science |
Link to License: | In Copyright |
GRUST, Torsten, Joachim KRÖGER, Dieter GLUCHE, Andreas HEUER, Marc H. SCHOLL, 1997. Query Evaluation in CROQUE : Calculus and Algebra Coincide. In: Proceedings of the 15. British National Conference on Databases
@inproceedings{Grust1997Query-6023, title={Query Evaluation in CROQUE : Calculus and Algebra Coincide}, year={1997}, booktitle={Proceedings of the 15. British National Conference on Databases}, author={Grust, Torsten and Kröger, Joachim and Gluche, Dieter and Heuer, Andreas and Scholl, Marc H.} }
Query_evaluation_1997.pdf | 265 |