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The semantics of incomplete databases as an expression of preferences

Véronique Royer
1991 Theoretical Computer Science  
., The semantics of incomplete databases as an expression of preferences, Theoretical Computer Science 78 (1991) 113-136.  ...  We argue that it is convenient to define an incomplete database as a double entity: an underlying incomplete database together with selection criteria, formally some preference relation on the set of models  ...  The idea was to formalize the control (or reduction) of incompleteness as an expression of some preferences among the models of the underlying database.  ... 
doi:10.1016/0304-3975(51)90005-9 fatcat:2lzs62ddbvfm3c7agtdiwgdcui

Page 2216 of Mathematical Reviews Vol. , Issue 92d [page]

1992 Mathematical Reviews  
We give conditions which are necessary and sufficient to ensure safety.” 92d:68043 68P15 Royer, Véronique (F-ONCE) The semantics of incomplete databases as an expression of preferences.  ...  A large class of nonmonotonic logics can be expressed as preference logics in a simple and unified manner.  ... 

Fuzzy querying of incomplete, imprecise, and heterogeneously structured data in the relational model using ontologies and rules

P. Buche, C. Dervin, O. Haemmerle, R. Thomopoulos
2005 IEEE transactions on fuzzy systems  
To deal with heterogeneity, MIEL queries the database through several views simultaneously. To query incomplete data, MIEL proposes to use a fuzzy set, expressing the query preferences of the user.  ...  Fuzzy sets may be defined on a hierarchized domain of values, called an ontology (values of the domain are connected using the a kind of semantic link).  ...  We call such a domain, an ontology. • process the fuzzy query in several views to retrieve information heterogeneously structured in the database; • define precisely preferences expressed as fuzzy sets  ... 
doi:10.1109/tfuzz.2004.841736 fatcat:4clwrdgk7nfbdkm5sqzyewo3eq

Inductive Reasoning and Machine Learning for the Semantic Web

Claudia d'Amato, Nicola Fanizzi, Marko Grobelnik, Agnieszka Lawrynowicz, Vojtech Svatek
2014 Semantic Web Journal  
Hence, the problem of mining from the Semantic Web currently becomes as important as it used to be that of data mining from local databases.  ...  The Semantic Web is supposed to provide a medium to share such information and is often perceived to be a global, distributed database of meaningfully represented data.  ... 
doi:10.3233/sw-130103 fatcat:5pqeikfjvndslm7vt4luwl7tqi

Querying disjunctive databases through nonmonotonic logics

Piero A. Bonatti, Thomas Eiter
1996 Theoretical Computer Science  
Query languages for retrieving information from disjunctive databases are an interesting open area of research.  ...  The expressive power of the languages that we consider has been explored in the context of relational databases.  ...  Acknowledgements The authors would like to thank Georg Gottlob for numerous discussions and his important suggestions, which had a strong influence on this work, Mirek Truszczytiski for his valuable hints  ... 
doi:10.1016/0304-3975(95)00192-1 fatcat:knpw5am77fbxtd557mlq64uxli

Page 4936 of Mathematical Reviews Vol. , Issue 99g [page]

1999 Mathematical Reviews  
They show that in this case the standard semantics and the active-domain semantics are equally expressive. Moreover, they provide an algorithm which permits translation between both semantics.  ...  Second, the authors consider Boolean queries expressible as first- order sentences consisting of linear equations and inequalities over the real numbers only.  ... 

The HySpirit retrieval platform

Thomas Rölleke, Ralf Lübeck, Gabriella Kazai
2001 Proceedings of the 24th annual international ACM SIGIR conference on Research and development in information retrieval - SIGIR '01  
platform possessing the advantages and expressiveness of database models, and the aggregation of uncertain evidence as defined by probability theory.  ...  searching and browsing. • Support retrieval strategies exploiting relationships (spatial, temporal, semantic etc.). • Consider intrinsic features of knowledge such as uncertainty, incompleteness and inconsistency  ...  platform possessing the advantages and expressiveness of database models, and the aggregation of uncertain evidence as defined by probability theory.  ... 
doi:10.1145/383952.384095 dblp:conf/sigir/RollekeLK01 fatcat:tcm3lndckzew7m5eypuy6uqlye

Preferentially Annotated Regular Path Queries [chapter]

Gösta Grahne, Alex Thomo, William Wadge
2006 Lecture Notes in Computer Science  
In all of these, we obtain important positive results, which encourage the use of our preference framework for enhanced querying of semistructured databases.  ...  Annotated regular path queries are expressed syntactically as annotated regular expressions.  ...  Seen from a different angle, regular path queries provide the user with a simple way of expressing preferences for navigating database paths. Let us take an example from road network databases.  ... 
doi:10.1007/11965893_22 fatcat:bb5ddwdxk5ct7ivvvpu7tbsc5m

Conversational querying

Yannis E. Ioannidis, Stratis D. Viglas
2006 Information Systems  
Disambiguation is achieved by using various types of semantic information. The overall method works independently of the domain under which it is used (i.e., independently of the database schema).  ...  During the course of a conversation, the preceding interaction is used as a context within which many incomplete and/or incremental phrases are uniquely and unambiguously interpreted, sparing the need  ...  Acknowledgements We are indebted to the anonymous reviewers for a large number of useful comments in the earlier versions of this paper. We would also like to thank Dr. Anya Sotiropoulou, Dr.  ... 
doi:10.1016/ fatcat:xnkqej3vhrbefa3kukrz4r64ci

Data Integration and Answer Set Programming [chapter]

Thomas Eiter
2005 Lecture Notes in Computer Science  
The rapid expansion of the Internet and World Wide Web led to growing interest in data and information integration, which should be capable to deal with inconsistent and incomplete data.  ...  We discuss why data integration can be an interesting model application of Answer Set programming, reviewing valuable features of non-monotonic logic programs in this respect, and emphasizing the role  ...  The views expressed here are, however, personal and not necessarily in line with those of INFOMIX folks.  ... 
doi:10.1007/11546207_2 fatcat:aqoiuvrci5bnlcszod2cr2mhta

Databases and Artificial Intelligence [chapter]

Nicole Bidoit, Patrick Bosc, Laurence Cholvy, Olivier Pivert, Marie-Christine Rousset
2020 A Guided Tour of Artificial Intelligence Research  
in the expression of preferences in database queries.  ...  This shows an additional cause for the possible 797 incompleteness of the answers, which is the limit of the expressive power of the 798 language for specifying the rewritings.  ... 
doi:10.1007/978-3-030-06170-8_3 fatcat:j6kir5iut5glxlpntvdp7mdake

Partial results in database systems

Willis Lang, Rimma V. Nehme, Eric Robinson, Jeffrey F. Naughton
2014 Proceedings of the 2014 ACM SIGMOD international conference on Management of data - SIGMOD '14  
We explore ways to characterize and classify these partial results, and describe an analytical framework that allows the system to perform coarse to fine-grained analysis to determine the semantics of  ...  As the size and complexity of analytic data processing systems continue to grow, the effort required to mitigate faults and performance skew has also risen.  ...  Intuitively, if an expression computes a value using Noncredible values as input, then the output is also Non-credible.  ... 
doi:10.1145/2588555.2612176 dblp:conf/sigmod/LangNRN14 fatcat:mj5p3ubbqbbwxkoiclpwccyo7a

Incomplete data

Leonid Libkin
2014 Proceedings of the 33rd ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '14  
, check whetherϕ D |= Q(t) ◮An older approach, from the 1980s, advocated by Reiter ◮ A database D is viewed as a formula ϕ D , or even a theory ◮ Query answering becomes logical implication.  ...  ◮ An older approach, from the 1980s, advocated by Reiter ◮ A database D is viewed as a formula ϕ D , or even a theory ◮ Query answering becomes logical implication.To see if Q(t) is true with certainty  ...  Adding knowledge A set F of formulae ϕ that may hold in database objects. A minimal requirement: [[D] ] can be described by a formula.  ... 
doi:10.1145/2594538.2594561 dblp:conf/pods/Libkin14 fatcat:bxl22q3y5naxpfdrk3m6bnkwq4

Certain answers as objects and knowledge

Leonid Libkin
2016 Artificial Intelligence  
The standard way of answering queries over incomplete databases is to compute certain answers, defined as the intersection of query answers on all complete databases that the incomplete database represents  ...  We describe the framework in the most general way, applicable to a variety of data models, and test it on three concrete relational semantics of incompleteness: open, closed, and weak closed world.  ...  Assume that the semantics [[D] ] of an incomplete database D is given as the set of all complete databases D which D can represent.  ... 
doi:10.1016/j.artint.2015.11.004 fatcat:reiva53vmrdv5hscjtnpvze4p4

The Semantic Web Languages [chapter]

Fausto Giunchiglia, Feroz Farazi, Letizia Tanca, Roberto De Virgilio
2009 Semantic Web Information Management  
The Semantic Web is basically an extension of the Web and of the Web-enabling database and Internet technology, and, as a consequence, the Semantic Web methodologies, representation mechanisms and logics  ...  Semantic Web, and then highlight a few fundamental differences which make the database and Semantic Web paradigms complementary but somehow difficult to integrate.  ...  an instance of a concept, owl:sameAs to state that two instances refer the same thing.  ... 
doi:10.1007/978-3-642-04329-1_3 fatcat:nzifw26awbcflp4hi75ygv4hw4
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