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Querying logical databases

Moshe Y. Vardi
1986 Journal of computer and system sciences (Print)  
We describe an approximation algorithm for query evaluation that enables one to implement a logical database on the top of a standard database management system.  ...  We study here the complexity of evaluating quaries in logical databases. We focus on Reither's model of closed-world databases with unknown values.  ...  query evaluation over logical databases to query evaluation over physical databases.  ... 
doi:10.1016/0022-0000(86)90016-4 fatcat:fflk7sbw2fbn7mmmo6zyhz6t74

Querying logical databases

Moshe Y. Vardi
1985 Proceedings of the fourth ACM SIGACT-SIGMOD symposium on Principles of database systems - PODS '85  
We describe an approximation algorithm for query evaluation that enables one to implement a logical database on the top of a standard database management system.  ...  We study here the complexity of evaluating quaries in logical databases. We focus on Reither's model of closed-world databases with unknown values.  ...  query evaluation over logical databases to query evaluation over physical databases.  ... 
doi:10.1145/325405.325413 dblp:conf/pods/Vardi85 fatcat:nbevnehxkrbjznrfjxwqjdmqf4

Logical Querying of Relational Databases

Luminita Pistol, Radu BUCEA-MANEA-TONIS
2016 Journal of Economic Development, Environment and People  
After a short introduction in propositional and first order logic, we implement dynamically a small database and translate some SQL queries in filtered java 8 streams, enhanced with Tuples facilities from  ...  This paper aims to demonstrate the usefulness of formal logic and lambda calculus in database programming.  ...  A logical query is the action of evaluating a Boolean expression concerning tuples and relations.  ... 
doi:10.26458/jedep.v5i4.518 fatcat:nvmzxhlcungc3ba6h7t4qn525i

Temporal Logic in Database Query Languages [chapter]

Hans Hinterberger, Josep Domingo-Ferrer, Vipul Kashyap, Vijay Khatri, Richard T. Snodgrass, Paolo Terenziani, Manolis Koubarakis, Yue Zhang, James B. D. Joshi, Johann Gamper, Michael Böhlen, Christian S. Jensen (+145 others)
2009 Encyclopedia of Database Systems  
This logic can be used as a natural temporal query language for point-stamped temporal databases. A query (a temporal logic formula) is evaluated with respect to an evaluation point (time instant).  ...  In this way, it becomes possible to refer in a single query to multiple snapshots of a given temporal database.  ...  [3] initiated the study of temporal-logic integrity constraints in relational databases. Tuzhilin and Clifford [12] considered temporal logic as a query language for temporal databases.  ... 
doi:10.1007/978-0-387-39940-9_402 fatcat:hgn3osgehngovi5qcztaro3ube

Querying disjunctive databases through nonmonotonic logics

Piero A. Bonatti, Thomas Eiter
1996 Theoretical Computer Science  
queries, while preference-based logics cannot.  ...  Query languages for retrieving information from disjunctive databases are an interesting open area of research.  ...  Such Boolean queries model yes/no queries on disjunctive databases. Boolean queries naturally correspond to database properties.  ... 
doi:10.1016/0304-3975(95)00192-1 fatcat:knpw5am77fbxtd557mlq64uxli

Querying TSQL2 databases with temporal logic [chapter]

Michael H. Böhlen, Jan Chomicki, Richard T. Snodgrass, David Toman
1996 Lecture Notes in Computer Science  
The translation from temporal logic to TSQLZ developed here enables a user to write high-level queries which can be evaluated against a spaceefficient representation of the database.  ...  We demonstrate that temporal logic is equal in expressive power to a syntactically defined subset of TSQL2.  ...  The semantics of temporal logic queries is defined with respect to sequences of database states [GHR94] . In temporal databases we do not want to construct and store all the states explicitly.  ... 
doi:10.1007/bfb0014161 fatcat:wl7ifei6qbccnk4icgcm7krqly

Database query languages and functional logic programming

Jesús M. Almendros-Jiménez, Antonio Becerra-Terón
2006 New generation computing  
To use functional logic programming as a database programming language, (1) we will propose a data model involving the main features adopted from functional logic programming (for instance, handling of  ...  Moreover, as most database systems, (4) we will propose an extended relational calculus and algebra, which can be used as alternative query languages in this framework.  ...  Like the functional logic query language, and as usual in the database query formalisms, we need to ensure the property of domain independence in the proposed calculus.  ... 
doi:10.1007/bf03037296 fatcat:nrklsenccja7pajdh25aitveam

Logic-based query optimization for object databases

J. Grant, J. Gryz, J. Minker, L. Raschid
2000 IEEE Transactions on Knowledge and Data Engineering  
We obtain equivalent (optimized) logic queries and, subsequently, obtain equivalent (optimized) OQL queries for each equivalent logic query.  ...  We demonstrate this technique for ODMG database schemas defined in ODL and object queries expressed in OQL. The object schema is represented using a logical representation (Datalog).  ...  His interests include database query optimization, heterogeneous database systems, and logic programming.  ... 
doi:10.1109/69.868906 fatcat:3bdgg4rolvg2pcmpj43s3fr4am

Query Optimization Using Fuzzy Logic in Integrated Database

Susana Susana, Suharjito Suharjito
2016 Indonesian Journal of Electrical Engineering and Computer Science  
<p>Query optimization in integrated database can't be separated from data processing method. In order to have faster query response time, a method to optimize queries is required.  ...  One of many methods that can be used for query optimization is using fuzzy logic with Tsukamoto inference system.  ...  Raipukar perform optimization in distributed databases by using fuzzy logic role. Queries on distributed data are expressed in the form of relational calculus relations resulting fuzzy queries [3] .  ... 
doi:10.11591/ijeecs.v4.i3.pp637-642 fatcat:zszrelrvzvhijk3j7hlkwgk54u

Natural Language Query Parser using First Order Logic for Querying Relational Databases

B. Sujatha, S. Viswanadha
2016 International Journal of Computer Applications  
The parser converts the Natural Language query into First order Logic and then the First order logic query is converted into structured query.  ...  Hence there is a need to construct a bridge between natural language query and database understandable query which is a major challenge.  ...  To get the required information from the database, the logic query is to be transformed into a structured query which is supported by the underlying Database Management System.  ... 
doi:10.5120/ijca2016908176 fatcat:vuqwevkpbrb63h4sarzx54arcu

Querying Inductive Databases via Logic-Based User-Defined Aggregates [chapter]

Fosca Giannotti, Giuseppe Manco
1999 Lecture Notes in Computer Science  
We show h o w a logic-based database language can support the various steps of the KDD process by providing: a high degree of expressiveness, the ability to formalize the overall KDD process and the capability  ...  In our proposal, deductive databases resemble relational databases while user deaened aggregates provided by the deductive database language resemble the mining function and results.  ...  Logic Database Languages Deductive databases are database management systems whose query languages and storage structures are designed around a logical model of data.  ... 
doi:10.1007/978-3-540-48247-5_14 fatcat:lsodhksdcbc63g3ttsa7acop7q

Generalized Pr�cis Queries for Logical Database Subset Creation

Alkis Simitsis, Georgia Koutrika, Yannis Ioannidis
2007 2007 IEEE 23rd International Conference on Data Engineering  
Précis queries are free-form queries that generate entire multirelation databases, which are logical subsets of existing ones.  ...  This paper is concerned with the definition and generation of logical database subsets based on précis queries under a generalized perspective that removes several restrictions of previous work and handles  ...  We described algorithms that generalize the functionality and optimize the performance of précis queries, as the experiments conducted indicate.  ... 
doi:10.1109/icde.2007.369017 dblp:conf/icde/SimitsisKI07 fatcat:6ipks2ivqvbznjf62lq4fzayyu

An inductive logic programming query language for database mining [chapter]

Luc De Raedt
1998 Lecture Notes in Computer Science  
Keywords : database mining query language, inductive logic programming, relational learning, inductive query language, data mining.  ...  First, a short introduction to inductive logic programming and machine learning is presented and then an inductive database mining query language RDM (Relational Database Mining language).  ...  Acknowledgements The author is supported by the Fund for Scientific Research, Flanders, and by the ESPRIT IV project no 20237 on Inductive Logic Programming II.  ... 
doi:10.1007/bfb0055898 fatcat:7k7wix3awndifapd3bzxfk5gkq

A paraconsistent logic programming approach for querying inconsistent databases

Sandra de Amo, Mônica Sakuray Pais
2007 International Journal of Approximate Reasoning  
In this paper, we use a paraconsistent logic (LFI1) as the underlying logic for the specification of P-Datalog, a deductive query language for databases containing inconsistent information.  ...  We present a declarative semantics which captures the desired meaning of a recursive query executed over a database containing inconsistent facts and whose rules allow inferring information from inconsistent  ...  Rather than classical first-order logic, P-Datalog uses the paraconsistent logic LFI1 as its underlying logic, and P-Datalog queries apply over paraconsistent databases.  ... 
doi:10.1016/j.ijar.2006.09.009 fatcat:tezgi5pygfeldi4klw5nauivy4

Temporal versus first-order logic to query temporal databases

Serge Abiteboul, Laurent Herr, Jan Van den Bussche
1996 Proceedings of the fifteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems - PODS '96  
The temporal database can then be queried using standard relational calculus ( rst-order logic) on this \timestamp" representation.  ...  We prove here that there are rst-order logic queries on the timestamp representation that are not expressible in (extended) temporal logic.  ...  Using (two-sorted) rst-order logic on the timestamp representation of a temporal database, we obtain a query language that is denoted by ts-fo.  ... 
doi:10.1145/237661.237674 dblp:conf/pods/AbiteboulHB96 fatcat:vczt4g7j2fbiffb42jw32qoqmy
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