DocumentCode :
1919357
Title :
Relational division: four algorithms and their performance
Author :
Graefe, Goetz
Author_Institution :
Oregon Graduate Center, Beaverton, OR, USA
fYear :
1989
fDate :
6-10 Feb 1989
Firstpage :
94
Lastpage :
101
Abstract :
Three known algorithms for relational division, the algebra operator used to express universal quantification (for-all conditions) and an algorithm called hash-division are outlined. By comparing the algorithms analytically and experimentally, it is shown that the algorithm provides performance competitive with or superior to that of techniques used to date, namely techniques using sorting or aggregate functions. Furthermore, the algorithm can eliminate duplicates in the divisor on the fly, ignores duplicates in the dividend, and allows two kinds of partitioning, either of which can be used to resolve hash table overflow or to efficiently implement the algorithm on a multiprocessor system
Keywords :
distributed databases; relational databases; algebra operator; duplicate elimination; hash table overflow; hash-division; multiprocessor system; partitioning; query processing; relational division; universal quantification; Aggregates; Algebra; Algorithm design and analysis; Data preprocessing; Database systems; Logic programming; Partitioning algorithms; Performance analysis; Relational databases; Sorting;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Data Engineering, 1989. Proceedings. Fifth International Conference on
Conference_Location :
Los Angeles, CA
Print_ISBN :
0-8186-1915-5
Type :
conf
DOI :
10.1109/ICDE.1989.47204
Filename :
47204
Link To Document :
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