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Independence in Database Relations
2013We investigate the implication problem for independence atoms X⊥Y of disjoint attribute sets X and Y on database schemata. A relation satisfies X⊥Y if for every X-value and every Y-value that occurs in the relation there is some tuple in the relation in which the X-value occurs together with the Y-value.
Kontinen, J., Link, S., Väänänen, J.
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A Method for Rough Relational Database Transformed into Relational Database
2009 IITA International Conference on Services Science, Management and Engineering, 2009It is decomposed the data of rough relational database and transformed into relational database according to the characteristic of rough relational database and relational database and in virtue of multiplication principle and Descartes of basic operation of relational algebra. Then deleted redundant data and optimized RDB.
Wei Zhang, Ling-ling Wei
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The use of a database machine for supporting relational databases
ACM SIGARCH Computer Architecture News, 1978One of the goals in the design of database machines of the future is their generality. In addition to being capable of carrying out the common database management functions with high reliability and performance, some of these machines are intended to support more than one data model. A specific database machine, known as the DBC, is intended to support
Jayanta Banerjee, David K. Hsiao
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Bubbles for relational database
ACM SIGARCH Computer Architecture News, 1978The mechanical disk storage is limited by long initial delay, few inputs/outputs, and serial access, thus necessitating large complex programs in existing database systems in order to map the user's view into the physical storage and to provide different access paths in response to different queries.
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On Normalization of Relations in Relational Databases
Programming and Computer Software, 2002zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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, 2013 In mathematics a binary relation between two sets \(A\) and \(B\) is a collection of ordered pairs \((a,b)\) belonging to the cartesian product \(A\,\times \,B\). In this chapter we present some of the general properties of relations and their operations, as well some special types of relations defined over the same set.
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Physical database design for relational databases
ACM Transactions on Database Systems, 1988This paper describes the concepts used in the implementation of DBDSGN, an experimental physical design tool for relational databases developed at the IBM San Jose Research Laboratory. Given a workload for System R (consisting of a set of SQL statements and their execution frequencies), DBDSGN suggests physical configurations for efficient performance.
Paolo Tiberio +2 more
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Construction of relations in relational databases
ACM Transactions on Database Systems, 1980Using a nonprocedural language for query formulation requires certain automatization of a query answering process. Given a query for creation of a new relation, the problem is to find an efficient procedure which produces this relation from a given relational database. We concentrate upon sequences of join operations which losslessly produce a relation
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