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Validation of Mappings Between Data Models
Validation of Mappings Between Data Models

... • Mapping inference allows us to check for redundant mapping formulas. • Mapping losslessness allows us to check whether some data is captured by mapping. It is a generalization of query answerability. • Query answerability checks whether the exact answer of a query is preserved by mapping. • Mappin ...
Lecture - 01 - Human Quotient
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Databases: Design, Implementation, and Management
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... Real Library Data (50 million RDF triples) Data acquired from a variety of diverse sources ...
ACM Proceedings Template - WORD
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... To get a quick estimate of the prevalence of security problems in actual code, we used Google’s code search [5], and searched for the strings pg_query (for the function used to execute dynamic SQL queries against a postgreSQL database), and pg_query_params (used to execute prepared statements). The ...
Introduction to Object Oriented Databases
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Data Resource Management - Pohang University of Science
Data Resource Management - Pohang University of Science

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original - Kansas State University
original - Kansas State University

...  OLAP implementations using only relational database features are called relational OLAP (ROLAP) systems  Hybrid systems, which store some summaries in memory and store the base data and other summaries in a relational database, are called hybrid OLAP (HOLAP) systems. ...
Basic Marketing, 16e
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department of computer sceinece - Kasturba Gandhi College for
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PowerPoint Chapter 3
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Chapter 3 - Personal Web Pages
Chapter 3 - Personal Web Pages

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Ontology-Based Computing
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white paper a comparison between relational and
white paper a comparison between relational and

... claimed that their products were relational. E.F. Codd responded by releasing a set of 12 rules that should be satisfied by any system claiming to be relational. Unfortunately, these rules excluded all systems then available, even systems like SQL which were based directly on Codd's relational calcu ...
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... • An OODBMS is a DBMS that directly supports a model based on the objectoriented paradigm. – Like any DBMS it must provide persistent storage for objects and their descriptions (schema). – The system must also provide a language for schema definition and and for manipulation of objects and their sch ...
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... – for extracting a substantial part or the whole content of the database, if the scientific work needs the treatment of a substantial part of the database (i.e. in case of statistic computation on large series of data), – in that case, it would be necessary to negotiate a specific agreement with the ...
CHAPTER 1: The Roles of Data and Database Administrators
CHAPTER 1: The Roles of Data and Database Administrators

...  When the error data have been processed, the db may be recovered in one of the ff ways: a. If the error is discovered soon enough, backward recovery may be used. b. If only a few errors have occurred, a series of compensating transactions may be introduced through human intervention to correct the ...


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I, and X
I, and X

... Examines existing facts and rules, and add new facts when possible. 2- Control: Decides the order in which inference are made. ...
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Relational model



The relational model for database management is an approach to managing data using a structure and language consistent with first-order predicate logic, first described in 1969 by Edgar F. Codd. In the relational model of a database, all data is represented in terms of tuples, grouped into relations. A database organized in terms of the relational model is a relational database.The purpose of the relational model is to provide a declarative method for specifying data and queries: users directly state what information the database contains and what information they want from it, and let the database management system software take care of describing data structures for storing the data and retrieval procedures for answering queries.Most relational databases use the SQL data definition and query language; these systems implement what can be regarded as an engineering approximation to the relational model. A table in an SQL database schema corresponds to a predicate variable; the contents of a table to a relation; key constraints, other constraints, and SQL queries correspond to predicates. However, SQL databases deviate from the relational model in many details, and Codd fiercely argued against deviations that compromise the original principles.
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