Finding equivalent rewritings in the presence of arithmetic comparisons

Afrati, F; Chirkova, R; Gergatsoulis, M; Pavlaki, V

dc.contributor.author	Afrati, F	en
dc.contributor.author	Chirkova, R	en
dc.contributor.author	Gergatsoulis, M	en
dc.contributor.author	Pavlaki, V	en
dc.date.accessioned	2014-03-01T02:44:03Z
dc.date.available	2014-03-01T02:44:03Z
dc.date.issued	2006	en
dc.identifier.issn	0302-9743	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/31643
dc.subject	Conjunctive Queries	en
dc.subject	Data Management	en
dc.subject	Efficient Algorithm	en
dc.subject	Select Project Join	en
dc.subject.classification	Computer Science, Theory & Methods	en
dc.subject.other	Arithmetic comparisons (ACs)	en
dc.subject.other	Data-management problems	en
dc.subject.other	Enumeration algorithms	en
dc.subject.other	SQL	en
dc.subject.other	Algorithms	en
dc.subject.other	Computational complexity	en
dc.subject.other	Digital arithmetic	en
dc.subject.other	Information management	en
dc.subject.other	Problem solving	en
dc.subject.other	Query languages	en
dc.title	Finding equivalent rewritings in the presence of arithmetic comparisons	en
heal.type	conferenceItem	en
heal.identifier.primary	10.1007/11687238_55	en
heal.identifier.secondary	http://dx.doi.org/10.1007/11687238_55	en
heal.language	English	en
heal.publicationDate	2006	en
heal.abstract	The problem of rewriting queries using views has received significant attention because of its applications in a wide variety of data-management problems. For select-project-join SQL (a.k.a. conjunctive) queries and views, there are efficient algorithms in the literature, which find equivalent and maximally contained rewritings. In the presence of arithmetic comparisons (ACs) the problem becomes more complex. We do not know how to find maximally contained rewritings in the general case. There are algorithms which find maximally contained rewritings only for special cases such as when ACs are restricted to be semi-interval. However, we know that the problem of finding an equivalent rewriting (if there exists one) in the presence of ACs is decidable, yet still doubly exponential. This complexity calls for an efficient algorithm which will perform better on average than the complete enumeration algorithm. In this work we present such an algorithm which is sound and complete. Its efficiency lies in that it considers fewer candidate rewritings because it includes a preliminary test to decide for each view whether it is potentially useful in some rewriting. © Springer-Verlag Berlin Heidelberg 2006.	en
heal.publisher	SPRINGER-VERLAG BERLIN	en
heal.journalName	Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)	en
heal.bookName	LECTURE NOTES IN COMPUTER SCIENCE	en
dc.identifier.doi	10.1007/11687238_55	en
dc.identifier.isi	ISI:000237081600055	en
dc.identifier.volume	3896 LNCS	en
dc.identifier.spage	942	en
dc.identifier.epage	960	en