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Temporal Integrity Constraints
Temporal Integrity Constraints

... history of the domain of discourse and the system’s knowledge about that history [10]. Such types of constraints cannot be expressed in formalisms with only one notion of time. Temporal logics have been extended in different ways to increase their expressive power. Such extensions include fixpoint o ...
Failures in DBMS
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... sequence of transactions (reads and writes). To understand database recovery, we must first understand the concept of transaction integrity. ...
Hydrographic Data Management using GIS Technologies
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... such as points, lines, and areas, you can create features that more closely resemble real-world objects such as landmarks, aids to navigation, and limit areas. Features with relationships and rules are known as custom features. Custom features can be created without any programming using ArcGIS. Op ...
For SQL Server 2008
For SQL Server 2008

... © Copyright Notice: All rights reserved worldwide. No part of this book may be reproduced or copied or translated in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher, except for r ...
Why PowerPivot? - ProDataMan
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...  If one crashes, all crashes  Limited to the memory of the machine Most data you are crunching should have been already preprocessed at some level  Alleviate some of the work from the client machine ...
Chapter 7: Relational Database Design
Chapter 7: Relational Database Design

... First Normal Form (Contd.)  Atomicity is actually a property of how the elements of the ...
Click to Unit 4 of DDB
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... line failures.the first two errors are the responsibility of the computer network; we will not consider them further. Therefore, in our discussions of distributed DBMS reliability, we expect the underlying computer network hardware and software to ensure that two messages sent from a process at some ...
Chapter 3 - Spatial Database Group
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Data Sheet
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... the application tier. Applications access the cache tables using standard SQL and PL/SQL via JDBC, ODBC, ODP.NET, Oracle Call Interface (OCI) and Pro*C/C++ programming interfaces. Cache tables operate like regular relational tables inside the TimesTen database and are persistent and recoverable. Dur ...
Mandatory Access Control and Role
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... The U.S. government has been involved in developing security technology for computer and communications systems for some time. Although advances have been great, it is generally perceived that the current state of security technology has, to some extent, failed to address the needs of all[1][2]. Thi ...
DataGuard_for_RAC_migrations_v2 - Indico
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... • The Data Guard based migration procedure has been used this year at CERN: – we migrated all production and validation databases ~15 systems in total – we moved from RHEL 3 to RHEL 4 at the same ...
Database Performance Study - Information Systems Department
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... of different ways to correctly process the query. The best execution plan chosen by the query optimizer is called the query execution plan (QEP). To show some of the complexities involved, a few examples have been included in appendix 3. ...
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... These standards provide a common approach for defining, publishing, and using web services. The final, and probably the most important, SOA concept is composition of services into business processes. Services are composed in a particular order and follow a set of rules to provide support for busines ...
Classes para Manipulação de BDs 5
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Automatically Synthesizing SQL Queries from Input
Automatically Synthesizing SQL Queries from Input

... basic SQL idioms, Figure 4 shows an example query using our SQL subset. When designing the SQL subset, we focused on standard SQL features and excluded user-defined functions and vendorspecific features, such as the TOP keyword supported in Microsoft SQLServer. We discarded some standard SQL feature ...
The SQL Server Database Consolidation Appliance Reference
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... The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsof ...
Self-Driving Database Management Systems
Self-Driving Database Management Systems

... What is needed for a truly “self-driving” database management system (DBMS) is a new architecture that is designed for autonomous operation. This is different than earlier attempts because all aspects of the system are controlled by an integrated planning component that not only optimizes the system ...
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... Allow seamless storage, retrieval and exchange of data in spatially-enabled databases (queries with both homogonous and heterogeneous databases) across distributed systems, including network servers and the Internet for web-based systems. ...
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... • CURSOR_ALREADY_OPEN - A program attempts to open an already open cursor. A cursor must be closed before it can be reopened. • DUP_VAL_ON_INDEX - A program attempts to store duplicate values in a column that is constrained by a unique index. • INVALID_CURSOR - A program attempts a cursor operation ...
cayf12e_ppt_12
cayf12e_ppt_12

... Publishing as Prentice Hall Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall ...
Introduction to Client/Server Computing
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My DB and PHP Access slides
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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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