Zobrazeno 1 - 10
of 104
pro vyhledávání: '"Dirk Van Gucht"'
Publikováno v:
The Computer Journal. 64:789-811
Many graph query languages rely on composition to navigate graphs and select nodes of interest, even though evaluating compositions of relations can be costly. Often, this need for composition can be reduced by rewriting toward queries using semi-joi
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7abbf54e5a506aba1f4a1d585f11188d
https://doi.org/10.1093/comjnl/bxaa031
https://doi.org/10.1093/comjnl/bxaa031
Publikováno v:
Lecture Notes in Computer Science ISBN: 9783031113208
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e4850aebcf19458af8b3fbf8d60a34b9
https://doi.org/10.1007/978-3-031-11321-5_11
https://doi.org/10.1007/978-3-031-11321-5_11
Fragments of Tarski’s relation algebra form the basis of many versatile graph and tree query languages including the regular path queries, XPath, and SPARQL. Surprisingly, however, a systematic study of the relative expressive power of relation alg
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0ec09de13f752a21dd261d8129ced52a
http://hdl.handle.net/1942/37014
http://hdl.handle.net/1942/37014
Publikováno v:
Annals of Mathematics and Artificial Intelligence. 87:157-184
For any query language $\mathcal {F}$ , we consider three natural families of boolean queries. Nonemptiness queries are expressed as e ≠ ∅ with e an $\mathcal {F}$ expression. Emptiness queries are expressed as e = ∅. Containment queries are ex
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ea715e23d1216e4d87911528be72ad4b
https://doi.org/10.1007/s10472-019-09639-5
https://doi.org/10.1007/s10472-019-09639-5
Publikováno v:
PODS
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::491b4d4334db9cb3179681037d7cee11
https://doi.org/10.1145/3375395.3387723
https://doi.org/10.1145/3375395.3387723
Autor:
Marc Gyssens, Dirk Van Gucht, George H. L. Fletcher, Jelle Hellings, Jan Van den Bussche, Stijn Vansummeren, Yuqing Wu
Publikováno v:
Information systems, 89
Information Systems, 89:101467. Elsevier
Information Systems, 89:101467. Elsevier
Motivated by the continuing interest in the tree data model, we study the expressive power of downward navigational query languages on trees and chains. Basic navigational queries are built from the identity relation and edge relations using composit
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cdcc6266b6d23a831c51403005c92bb8
http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/296840
http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/296840
Publikováno v:
PODS
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::18e639e132182ff8e37a03e8ae98a8ef
https://doi.org/10.1145/3294052.3322193
https://doi.org/10.1145/3294052.3322193
Publikováno v:
Journal of computer and system sciences
Symmetric queries are introduced as queries on a sequence of sets of objects the result of which does not depend on the order of the sets. An appropriate data model is proposed, and two query languages are introduced, QuineCALC and SyCALC. They are c
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::519003f991c20f86143172a98ddd2e0a
https://hdl.handle.net/10067/1611700151162165141
https://hdl.handle.net/10067/1611700151162165141
Publikováno v:
Lecture Notes in Computer Science ISBN: 9783319900490
FoIKS
FoIKS
Fragments of Tarski’s relation algebra form the basis of many versatile graph and tree query languages including the regular path queries, XPath, and SPARQL. Surprisingly, however, a systematic study of the relative expressive power of relation alg
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2340021e1928c3d8bef75eecac12cad8
http://hdl.handle.net/1942/26656
http://hdl.handle.net/1942/26656