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Clustering-based fragmentation and data replication for flexible query answering in distributed databases

Lena Wiese
2014 Journal of Cloud Computing: Advances, Systems and Applications  
On the other hand, flexible query answering can enable a database system to find related information for a user whose original query cannot be answered exactly.  ...  In this paper we study a clustering-based fragmentation for the generalization operator Anti-Instantiation with which related information can be found in distributed data.  ...  The approach combines fragmentation based on a clustering with data replication. For the user, this approach is totally invisible: he can send queries to the database system unchanged.  ... 
doi:10.1186/s13677-014-0018-0 fatcat:2ya54sethrav5hryy3rzoe776u

Distributed database systems: where are we now?

M.T. Ozsu, P. Valduriez
1991 Computer  
Distributed database technology is expected to have a significant impact on data processing in the upcoming years.  ...  In this paper, we reflect on the promises of distributed database technology, take stock of where we are, and discuss the issues that remain to be solved.  ...  Capturing knowledge in the form of rules has been extensively studied in a particular form of knowledge base system called a deductive database.  ... 
doi:10.1109/2.84879 fatcat:y5fmci57j5d35irk6ftktqct3i

Predicate invention in inductive data engineering [chapter]

Peter A. Flach
1993 Lecture Notes in Computer Science  
The system is implemented in a deductive database framework, and can be viewed as an Inductive Logic Programming system with predicate invention capabilities.  ...  By inductive data engineering we mean the (interactive) process of restructuring a knowledge base by means of induction.  ...  A (deductive) database is a collection of intensional and extensional relations.  ... 
doi:10.1007/3-540-56602-3_129 fatcat:4dsn3bsjo5efjihgwh7iswolpq

RDF Storage and Retrieval Systems [chapter]

Alice Hertel, Jeen Broekstra, Heiner Stuckenschmidt
2009 Handbook on Ontologies  
In this chapter, we review RDF storage and retrieval technologies as a common approach for accessing ontology-based data.  ...  We discuss different storage models, typical functionalities of RDF middleware such as data model support and reasoning capabilities and RDF query languages with a special focus on SPARQL as an emerging  ...  Compute and store the deductive closure of a graph as a basis for querying. 2. Let a query processor infer new statements as needed per query.  ... 
doi:10.1007/978-3-540-92673-3_22 dblp:series/ihis/HertelBS09 fatcat:atuhk24ekbf5thcqsgeznuxyhu

Query Optimization in Database Systems

Matthias Jarke, Jurgen Koch
1984 ACM Computing Surveys  
Efficient methods of processing unanticipated queries are a crucial prerequisite for the success of generalized database management systems.  ...  A wide variety of approaches to improve the performance of query evaluation algorithms have been proposed: logic-based and semantic transformations, fast implementations of basic operations, and combinatorial  ...  Ullman [1982] describes the use of "guard conditions" for simplifying queries on horizontally distributed databases by identifying the relevant fragments.  ... 
doi:10.1145/356924.356928 fatcat:wbynstasonffngdckfza4ueudi

Specification-Guided Component-Based Synthesis from Effectful Libraries [article]

Ashish Mishra, Suresh Jagannathan
2022 arXiv   pre-print
If the nature of these effects are exposed as part of their specification, however, deductive synthesis approaches can be used to help guide the search for components.  ...  Component-based synthesis seeks to build programs using the APIs provided by a set of libraries.  ...  ACKNOWLEDGMENTS We thank the anonymous reviewers for their detailed comments and suggestions. Funding for this work material is supported in part by DARPA, under the Safe Documents (SafeDocs) program.  ... 
arXiv:2209.02752v1 fatcat:rwqptk6ig5garokh7j2edms4pe

Ontology-based end-user visual query formulation: Why, what, who, how, and which?

Ahmet Soylu, Martin Giese, Ernesto Jimenez-Ruiz, Evgeny Kharlamov, Dmitriy Zheleznyakov, Ian Horrocks
2016 Universal Access in the Information Society  
This article presents and argues for ontology-based visual query formulation for end users; discusses its feasibility in terms of ontology-based data access, which virtualises legacy relational databases  ...  Hence, there is a need for providing people who are not professional developers with the flexibility to pose relatively complex and ad hoc queries in an easy and intuitive way.  ...  This has been followed by a hybrid approach, referred to as object-deductive databases, which combines the representation capabilities of objectoriented databases and the reasoning power of deductive databases  ... 
doi:10.1007/s10209-016-0465-0 fatcat:ejbb5nrzgfegzjgub2cv3dsryy

Logic, Languages, and Rules for Web Data Extraction and Reasoning over Data [chapter]

Georg Gottlob, Christoph Koch, Andreas Pieris
2017 Lecture Notes in Computer Science  
We then present some complexity results for monadic Datalog over trees and for XPath query evaluation.  ...  This paper gives a short overview of specific logical approaches to data extraction, data management, and reasoning about data.  ...  ., whether a given diagram admits at least one model. Object-Oriented Deductive Databases.  ... 
doi:10.1007/978-3-319-53733-7_2 fatcat:wkewt6kjpjezpnh44g4pak5kqe

On the Logic of SQL Nulls

Enrico Franconi, Sergio Tessaris
2012 Alberto Mendelzon Workshop on Foundations of Data Management  
In the logic based approaches to modelling relational databases proposed so far, nulls are considered as representing unknown values.  ...  Moreover, we prove a faithful encoding of the logic into standard first-order logic, so that we can employ classical deduction machinery.  ...  We restrict our attention to the first-order fragment of SQL -e.g., we do not consider aggregates, and both queries and constraints should be set based (as opposed to bag/multi-set based): this fragment  ... 
dblp:conf/amw/FranconiT12 fatcat:i6gxluaatjhsphvidsex7f5w64

On the Termination of the Chase Algorithm [chapter]

Michael Meier
2010 Lecture Notes in Computer Science  
In Section 9.1 we develop a unied approach to typed-based and semantic query optimization techniques showing that both optimization tasks can be addressed using a single, logic-based framework, which seamlessly  ...  We present a unifying, logic-based framework for query optimization in the presence of data dependencies and type information.  ... 
doi:10.1007/978-3-642-15918-3_23 fatcat:wsougypcmrhmxm3s6choxxfssm


Alexandra Meliou, Dan Suciu
2012 Proceedings of the 2012 international conference on Management of Data - SIGMOD '12  
The contributions of this work are the following: (a) we define how-to queries using possible world semantics, and propose the specification language TiQL (for Tiresias Query Language) based on simple  ...  Mixed Integer Programming problems, on top of a relational database system.  ...  In TIRESIAS, users write a declarative query in the TIRESIAS query language (TiQL), which is a datalog-based language for how-to queries.  ... 
doi:10.1145/2213836.2213875 dblp:conf/sigmod/MeliouS12 fatcat:v37orjkbpzgz5hqynjmqviztxq

Information Integration and Computational Logic [article]

Yannis Dimopoulos, Antonis Kakas
2001 arXiv   pre-print
Information from disparate heterogeneous sources often with no a-priori common schema needs to be synthesized in a flexible, transparent and intelligent way in order to respond to the demands of a query  ...  It stands at the crossroad of Databases and Artificial Intelligence requiring novel techniques that bring together different methods from these fields.  ...  Mimmo Sacca, the coordinator of Compulog-Net for the area Logic-based Databases, has helped in collecting material and in forming the structure of this survey.  ... 
arXiv:cs/0106025v1 fatcat:u275rpw5i5c3xg7jjn636y53um

Index—Volumes 1–89

1997 Artificial Intelligence  
502 epistemic -1142 from an agent 1358 in databases evaluation of -338 nonterminating -536 query 1257.1264 a knowledge base 13 11 about the system's behavior 659 query answering 1257 algorithm  ...  problem in geometry 470 set, restricted -1381 query system database -216 natural language -226 query-by-example 1037 query-directed simplification 918 querying a timegraph 1169 bounds1257  ... 
doi:10.1016/s0004-3702(97)80122-1 fatcat:6az7xycuifaerl7kmv7l3x6rpm

Using Partial Evaluation in Distributed Query Evaluation

Peter Buneman, Gao Cong, Wenfei Fan, Anastasios Kementsietsidis
2006 Very Large Data Bases Conference  
We develop this idea for the evaluation of boolean XPath queries over a tree that is fragmented, both horizontally and vertically over a number of sites.  ...  This approach has several advantages. First, each site is visited only once, even if several fragments of the tree are stored at that site.  ...  Its relevance to query evaluation has surfaced from time to time, most notably in the closely related areas of query rewriting with views and deductive databases [9] .  ... 
dblp:conf/vldb/BunemanCFK06 fatcat:rhd6rc3npzbdle3h5qhatw4idi

A logical semantics for hypothetical rulebases with deletion

Anthony J. Bonner
1997 The Journal of Logic Programming  
This paper addresses a limitation of most deductive database systems: they cannot reason hypothetically.  ...  Most previous work in this area has focused on the hypothetical insertion of facts into a database since insertion is accounted for by a well-established logic: intuitionistic logic.  ...  For the base case, observe that the expression R, DB F-4) is in ,4i = ci~(,4~-1) by Lemma 5.3, so it is in cli(,4 i-1) since 4) is positive.  ... 
doi:10.1016/s0743-1066(96)00093-3 fatcat:lhalyo6ih5cbrbnyusorzx3tlq
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