Online querying of d-dimensional hierarchies

Doka, K; Tsoumakos, D; Koziris, N

dc.contributor.author	Doka, K	en
dc.contributor.author	Tsoumakos, D	en
dc.contributor.author	Koziris, N	en
dc.date.accessioned	2014-03-01T01:36:34Z
dc.date.available	2014-03-01T01:36:34Z
dc.date.issued	2011	en
dc.identifier.issn	0743-7315	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/21344
dc.subject	Concept hierarchies	en
dc.subject	Data warehousing	en
dc.subject	Distributed hash tables	en
dc.subject	Peer-to-Peer	en
dc.subject.classification	Computer Science, Theory & Methods	en
dc.subject.other	Adaptive scheme	en
dc.subject.other	Communication overheads	en
dc.subject.other	Concept hierarchies	en
dc.subject.other	Data warehousing	en
dc.subject.other	Distributed Hash Table	en
dc.subject.other	Distributed storage	en
dc.subject.other	Distributed systems	en
dc.subject.other	Drill-down	en
dc.subject.other	Experimental evaluation	en
dc.subject.other	Load imbalance	en
dc.subject.other	Multidimensional data	en
dc.subject.other	Peer to peer	en
dc.subject.other	Prior knowledge	en
dc.subject.other	Query flooding	en
dc.subject.other	Systems analysis	en
dc.subject.other	Warehouses	en
dc.subject.other	Data warehouses	en
dc.title	Online querying of d-dimensional hierarchies	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.jpdc.2010.10.005	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.jpdc.2010.10.005	en
heal.language	English	en
heal.publicationDate	2011	en
heal.abstract	In this paper we describe a distributed system designed to efficiently store, query and update multidimensional data organized into concept hierarchies and dispersed over a network. Our system employs an adaptive scheme that automatically adjusts the level of indexing according to the granularity of the incoming queries, without assuming any prior knowledge of the workload. Efficient roll-up and drill-down operations take place in order to maximize the performance by minimizing query flooding. Updates are performed on-line, with minimal communication overhead, depending on the level of consistency needed. Extensive experimental evaluation shows that, on top of the advantages that a distributed storage offers, our method answers the vast majority of incoming queries, both point and aggregate ones, without flooding the network and without causing significant storage or load imbalance. Our scheme proves to be especially efficient in cases of skewed workloads, even when these change dynamically with time. At the same time, it manages to preserve the hierarchical nature of data. To the best of our knowledge, this is the first attempt towards the support of concept hierarchies in DHTs. (C) 2010 Elsevier Inc. All rights reserved.	en
heal.publisher	ACADEMIC PRESS INC ELSEVIER SCIENCE	en
heal.journalName	Journal of Parallel and Distributed Computing	en
dc.identifier.doi	10.1016/j.jpdc.2010.10.005	en
dc.identifier.isi	ISI:000286701700008	en
dc.identifier.volume	71	en
dc.identifier.issue	3	en
dc.identifier.spage	424	en
dc.identifier.epage	437	en