Linearisability on datalog programs

Afrati, F; Gergatsoulis, M; Toni, F

dc.contributor.author	Afrati, F	en
dc.contributor.author	Gergatsoulis, M	en
dc.contributor.author	Toni, F	en
dc.date.accessioned	2014-03-01T01:19:10Z
dc.date.available	2014-03-01T01:19:10Z
dc.date.issued	2003	en
dc.identifier.issn	0304-3975	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/15383
dc.subject	Database queries	en
dc.subject	Datalog programs	en
dc.subject	Deductive databases	en
dc.subject	Linearisability	en
dc.subject	Program optimisation	en
dc.subject	Program transformation	en
dc.subject.classification	Computer Science, Theory & Methods	en
dc.subject.other	Database systems	en
dc.subject.other	Mathematical transformations	en
dc.subject.other	Optimization	en
dc.subject.other	Query languages	en
dc.subject.other	Deductive databases	en
dc.subject.other	Computer software	en
dc.title	Linearisability on datalog programs	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0304-3975(02)00730-2	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0304-3975(02)00730-2	en
heal.language	English	en
heal.publicationDate	2003	en
heal.abstract	Linear Datalog programs are programs whose clauses have at most one intensional atom in their bodies. We explore syntactic classes of Datalog programs (syntactically non-linear) which turn out to express no more than the queries expressed by linear Datalog programs. In particular, we investigate linearisability of (database queries corresponding to) piecewise linear Datalog programs and chain queries: (a) We prove that piecewise linear Datalog programs can always be transformed into linear Datalog programs, by virtue of a procedure which performs the transformation automatically. The procedure relies upon conventional logic program transformation techniques. (b) We identify a new class of linearisable chain queries, referred to as pseudo-regular, and prove their linearisability constructively, by generating, for any given pseudo-regular chain query, the Datalog program corresponding to it. (C) 2002 Published by Elsevier B.V.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Theoretical Computer Science	en
dc.identifier.doi	10.1016/S0304-3975(02)00730-2	en
dc.identifier.isi	ISI:000186456500005	en
dc.identifier.volume	308	en
dc.identifier.issue	1-3	en
dc.identifier.spage	199	en
dc.identifier.epage	226	en