2026-07-22T11:56:49Z https://drops.dagstuhl.de/oai

oai:drops-oai.dagstuhl.de:13716 2024-03-06T10:52:30Z ddc:004 open_access

Input-Output Disjointness for Forward Expressions in the Logic of Information Flows Aamer, Heba Van den Bussche, Jan Composition expressive power variable substitution Last year we introduced the logic FLIF (forward logic of information flows) as a declarative language for specifying complex compositions of information sources with limited access patterns. The key insight of this approach is to view a system of information sources as a graph, where the nodes are valuations of variables, so that accesses to information sources can be modeled as edges in the graph. This allows the use of XPath-like navigational graph query languages. Indeed, a well-behaved fragment of FLIF, called io-disjoint FLIF, was shown to be equivalent to the executable fragment of first-order logic. It remained open, however, how io-disjoint FLIF compares to general FLIF . In this paper we close this gap by showing that general FLIF expressions can always be put into io-disjoint form. Schloss Dagstuhl – Leibniz-Zentrum für Informatik Heba Aamer and Jan Van den Bussche 2021 Is Part Of LIPIcs, Volume 186, 24th International Conference on Database Theory (ICDT 2021) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/LIPIcs.ICDT.2021.8 urn:nbn:de:0030-drops-137167 https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ICDT.2021.8 eng https://creativecommons.org/licenses/by/4.0/legalcode