Date of Award
4-1984
Degree Name
Master of Science
Department
Computer Science
First Advisor
Dr. Dionysios Kountanis
Second Advisor
Dr. Dalia Motzkin
Access Setting
Masters Thesis-Open Access
Abstract
In processing a Boolean query against a non-inverted file, a subset of the query's keys must be selected. Only the records satisfying these keys need to be retrieved from the file. A dynamic programming algorithm, the Dual-to-minDF, is developed here for arriving at the optimum set of keys, i.e., the minimum number of external record retrievals. Previously suggested greedy methods yield feasible solutions which may or may not be optimal. This algorithm has exponential time complexity. However, it is useful for applications involving relatively short queries with duplication of keys within different conjuncts, and in cases where the files have large numbers of records per keyword. This makes the trade-off of I/o savings vs. extra processing costs worth it. Possible extensions of this research are suggested.
Recommended Citation
Kaminski, Donna Marie, "A Query-Processing Optimization Strategy for Generalized File Structures" (1984). Masters Theses. 1535.
https://scholarworks.wmich.edu/masters_theses/1535