Managing lineage and uncertainty under a data exchange setting

Afrati, FN; Vasilakopoulos, A

dc.contributor.author	Afrati, FN	en
dc.contributor.author	Vasilakopoulos, A	en
dc.date.accessioned	2014-03-01T02:46:52Z
dc.date.available	2014-03-01T02:46:52Z
dc.date.issued	2010	en
dc.identifier.issn	03029743	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/32900
dc.subject	Data Exchange	en
dc.subject	Data Uncertainty	en
dc.subject	Lineage	en
dc.subject.other	Certain answers	en
dc.subject.other	Chase algorithm	en
dc.subject.other	Conjunctive queries	en
dc.subject.other	Data exchange	en
dc.subject.other	Data uncertainty	en
dc.subject.other	Equality-generating dependency	en
dc.subject.other	Lineage	en
dc.subject.other	NP-hard	en
dc.subject.other	Uncertain datas	en
dc.title	Managing lineage and uncertainty under a data exchange setting	en
heal.type	conferenceItem	en
heal.identifier.primary	10.1007/978-3-642-15951-0_9	en
heal.identifier.secondary	http://dx.doi.org/10.1007/978-3-642-15951-0_9	en
heal.publicationDate	2010	en
heal.abstract	We present a data exchange framework that is capable of exchanging uncertain data with lineage and give meaningful certain answers on queries posed on the target schema. The data are stored in a database with uncertainty and lineage (ULDB) which represents a set of possible instances that are databases with lineage (LDBs). Hence we need first to revisit all the notions related to data exchange for the case of LDBs. Producing all possible instances of a ULDB, like the semantics of certain answers would indicate, is exponential. We present a more efficient approach: a u-chase algorithm that extends the known chase procedure of traditional data exchange and show that it can be used to correctly compute certain answers for conjunctive queries in PTIME for a set of weakly acyclic tuple generating dependencies. We further show that if we allow equality generating dependencies in the set of constraints then computing certain answers for conjunctive queries becomes NP-hard. © 2010 Springer-Verlag Berlin Heidelberg.	en
heal.journalName	Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)	en
dc.identifier.doi	10.1007/978-3-642-15951-0_9	en
dc.identifier.volume	6379 LNAI	en
dc.identifier.spage	28	en
dc.identifier.epage	41	en