Title
Dynamic optimization of queries in pivot-based indexing
Abstract
This paper evaluates the use of standard database indexes and query processing as a way to do metric indexing in the LAESA approach. By utilizing B-trees and R-trees as pivot-based indexes, we may use well-known optimization techniques from the database field within metric indexing and search. The novelty of this paper is that we use a cost-based approach to dynamically evaluate which and how many pivots to use in the evaluation of each query. By a series of measurements using our database prototype we are able to evaluate the performance of this approach. Compared to using all available pivots for filtering, the optimized approach gives half the response times for main memory data, but much more varied results for disk resident data. However, by use of the cost model we are able to dynamically determine when to bypass the indexes and simply perform a sequential scan of the base data. The conclusion of this evaluation is that it is beneficial to create many pivots, but to use only the most selective ones during evaluation of each query. R-trees give better performance than B-trees when utilizing all pivots, but when being able to dynamically select the best pivots, B-trees often provide better performance.
Year
DOI
Venue
2012
10.1007/s11042-010-0614-z
Multimedia Tools Appl.
Keywords
Field
DocType
Similarity search,Pivot-based indexing,Database trees,Optimized query processing
Data mining,Information retrieval,Computer science,Full table scan,Filter (signal processing),Search engine indexing,Novelty,Database index,Nearest neighbor search
Journal
Volume
Issue
ISSN
60
2
1380-7501
Citations 
PageRank 
References 
3
0.38
18
Authors
2
Name
Order
Citations
PageRank
Svein Erik Bratsberg122833.00
Magnus Lie Hetland2738.04