|
|
|
@inproceedings{DBLP:conf/sigmod/DeWitt79,
author = {David J. DeWitt},
editor = {Philip A. Bernstein},
title = {Query Execution in DIRECT},
booktitle = {Proceedings of the 1979 ACM SIGMOD International Conference on
Management of Data, Boston, Massachusetts, May 30 - June 1},
publisher = {ACM},
year = {1979},
isbn = {0-89791-001-X},
pages = {13-22},
ee = {http://doi.acm.org/10.1145/582095.582098, db/conf/sigmod/DeWitt79.html},
crossref = {DBLP:conf/sigmod/79},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
In this paper query organization, execution, and optimization in the database machine DIRECT are discussed. We demonstrate that the use of a monitor for each relation referenced by a query along with the use of the NEXT PAGE construct permits the DIRECT back-end controller to assign a query to any number of processors for execution. Furthermore, these constructs also permit the controller to balance the load in the back-end by dynamically adjusting how many processors are assigned to each executing query.
We also identify the problem of relation fragmentation which occurs when a query is executed by several processors in parallel and develop a technique for estimating the optimal number of processors to compress a relation so that the execution time of the entire query is minimized. These results appear to be applicable to all database machines which employ parallel processing techniques to enhance query execution.
Copyright © 1979 by the ACM, Inc., used by permission. Permission to make digital or hard copies is granted provided that copies are not made or distributed for profit or direct commercial advantage, and that copies show this notice on the first page or initial screen of a display along with the full citation.
CDROM Version: Load the CDROM "Volume 1 Issue 2, SIGMOD '75-'92" and ...
