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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

A database system architecture supporting coexisting query languages and data models

Hepp, Pedro E. January 1983 (has links)
Database technology is already recognised and increasingly used in administering and organising large bodies of data and as an aid in developing software. This thesis considers the applicability of this technology in small but potentially expanding application environments with users of varying levels of competence. A database system architecture with the following main characteristics is proposed: Database technology is already recognised and increasingly used in administering and organising large bodies of data and as an aid in developing software. This thesis considers the applicability of this technology in small but potentially expanding application environments with users of varying levels of competence. A database system architecture with the following main characteristics is proposed:Database technology is already recognised and increasingly used in administering and organising large bodies of data and as an aid in developing software. This thesis considers the applicability of this technology in small but potentially expanding application environments with users of varying levels of competence. A database system architecture with the following main characteristics is proposed : 1. It is based on a set of software components that facilitates the implementation and evolution of a software development environment centered on a database. 2. It enables the implementation of different user interfaces to provide adequate perceptions of the information content of the database according to the user's competence, familiarity with the system or the complexity of the processing requirements. 3. it is oriented toward databases that require moderate resources from the computer system to start an application. Personal or small-group databases are likely to benefit most from this approach.
202

Database Forensics in the Service of Information Accountability

Pavlou, Kyriacos 04 November 2011 (has links)
Poster won first place in the graduate division of Physical Sciences, Mathematics, Computer Engineering and Computer Science at GPSC Student Showcase 2011. / Regulations and societal expectations have recently expressed the need to mediate access to valuable databases, even by insiders. At one end of the spectrum is the approach of restricting access to information and on the other that of information accountability. The focus of the proposed work is effecting information accountability of data stored in databases. One way to ensure appropriate use and thus end-to-end accountability of such information is tamper detection in databases via a continuous assurance technology based on cryptographic hashing. In our current research we are working to show how to develop the necessary approaches and ideas to support accountability in high performance databases. This will include the design of a reference architecture for information accountability and several of its variants, the development of forensic analysis algorithms and their cost model, and a systematic formulation of forensic analysis for determining when the tampering occurred and what data were tampered with. Finally, for privacy, we would like to create mechanisms for allowing as well as (temporarily) preventing the physical deletion of records in a monitored database. In order to evaluate our ideas we will design and implement an integrated tamper detection and forensic analysis system. This work will show that information accountability is a viable alternative to information restriction for ensuring the correct storage, use, and maintenance of databases.
203

Fixed Income Database Design & Architecture

Zeng, Hong 31 May 2005 (has links)
"No matter how good a portfolio manager is, she or he can not makes right investment decisions without the right information. It is all about data: how can many megabytes of data must be loaded into a continuously growing system, stored efficiently, and made easily accessible to all queries and to all applications? In this project, we build a decision database for managing a portfolio of fixed-income investments. We review the key features of the database architecture and describe key steps in processing the available date. In addition, we review some common analyses that are done by the portfolio manager by studying the report needed for a study of the investment duration at the sector level. "
204

Estudo e construção de um sistema gerenciador de banco de dados dedutivo / Study and construction of a deductive database management system

Nardon, Fabiane Bizinella January 1996 (has links)
Este trabalho apresenta o estudo e a construção de um Sistema Gerenciador de Bancos de Dados Dedutivos. Um Banco de Dados Dedutivo (BDD) é um Banco de Dados que, alem de sua parte tradicional, ou seja, as informações contidas nas relações básicas, que são explicitamente inseridas, possui um conjunto de regras dedutivas que permite derivar novas informações a partir das relações básicas. Neste trabalho, as deficiências da linguagem de consulta Datalog foram identificadas e, com o objetivo de obter uma linguagem que atenda melhor algumas das necessidades de aplicações do mundo real, foram propostas extensões ao Datalog, que deram origem a linguagem DEDALO. As atualizações sobre Bancos de Dados Dedutivos também foram estudadas, sendo identificados dois problemas: o primeiro se refere a necessidade de propagar modificações sobre as relações básicas para as relações derivadas materializadas; o segundo problema diz respeito as atualizações sobre as relações derivadas, que devem ser traduzidas em atualizações sobre as relações básicas, para que a atualização pretendida se tome visível na relação derivada. Para o primeiro problema, métodos de propagação foram estudados, analisados e implementados. Para o segundo, foram estudados, analisados, propostos e implementados métodos que realizam a tradução das atualizações. Restrições de integridade em Bancos de Dados Dedutivos tamb6m foram estudadas, sendo propostos métodos eficientes de detecção de violações de integridade e de reparos de transações que violam as restrições definidas no sistema. Os estudos realizados deram origem ao Sistema Gerenciador de Banco de Dados Dedutivo DEDALO, um protótipo que implementa a nova linguagem proposta Como uma extensão do Datalog, os métodos de propagação de atualizações para relações derivadas materializadas, as técnicas de tradução de atualizações sobre relações derivadas, os métodos de detecção de violação de restrições de integridade e as técnicas de reparo das transações que as violam. 0 Sistema DEDALO é composto de quatro ferramentas: o Gerenciador de Regras, onde as regras de derivação e as restrições de integridade são definidas; a Interface Interativa, utilizada para submeter consultas ad hoc e solicitações de atualização sobre o sistema; dois novos Componentes Delphi, que são duas novas classes criadas para o ambiente de desenvolvimento de aplicações Delphi, que foi utilizado na implementação do protótipo, e são utilizadas para a criação das aplicações sobre o Sistema DEDALO; e o Tradutor de Sentenças DEDALOISQL-ANSI, que traduz as sentenças da linguagem proposta para sentenças SQL-ANSI que serão submetidas ao Sistema Gerenciador do Banco de Dados. A adequabilidade das soluções estudadas e implementadas no sistema desenvolvido pode ser comprovada através da implementação de uma aplicação real utilizando o Sistema DEDALO. / This work presents the study and construction of a Deductive Database Management System. A Deductive Database (BDD) is a Database that; besides the traditional part, where the informations are contained in basic relations, explicitly introduced, has a deductive rules set, which permits to derive new informations from the basic relations. In this work, the deficiencies of Datalog language were identified and, with the goal of obtaining a language which could better support some real world applications requirements, extensions to Datalog were proposed, which originate the DEDALO language. Deductive Databases updates were also studied and two problems were identified: the first one refers to the need of propagating updates over basic relations to the materialized derived relations; the second problem refers to the updates over derived relations, which must be translated in updates over basic relations, in order that the requested update become visible in the derived relation. For the first problem, propagation methods were studied, analyzed and implemented. For the second, methods for carrying out updates translation were studied, analyzed, proposed and implemented. Integrity Constraints in Deductive Database Systems were also studied and methods were proposed in order to detect and repair system defined integrity constraints violations. Through the studies related above was created DEDALO Deductive Database Management System, a prototype that implements the new language, proposed as a Datalog extension. The prototype also contains the implementation of updates propagation methods for materialized derived relations, the translation techniques of updates over derived relations, the integrity constraints violation detection methods and the repairing techniques for the transactions that violate the constraints. The DEDALO System is composed of four tools: the Rules Manager, where derivation rules and integrity constraints are defined; the Interactive Interface, used for submit ad hoc queries and updates request to the system; two new Delphi Components, which are two new classes created for the application development environment Delphi, which was used in the prototype implementation, and are used in the applications creation over the DEDALO System; and the DEDALO/SQL-ANSI Statements Translator, which translate the statements of the proposed language to SQL-ANSI statements, which will be submitted to the Database Management System. The adequacy of the solutions studied and implemented in the prototype system was verified by the implementation of an application using the DEDALO System.
205

The Customized Database Fragmentation Technique in Distributed Database Systems : A case Study

Shareef, Mohammed Ibrahim, Rawi, Aus Wail-Al January 2012 (has links)
In current age, various companies are using a centralized database system for dailybusiness transactions in different domains. Some critical issues have been observedrelated to the complexity, maintenance, performance and communication cost of datain centralized data repository for query processing, according to the demand of endusersfrom different locations. So, different enterprises are striving to implementefficient distributed database systems in their business environments for scalability.The distributed database architecture covers different factors such as transparentmanagement system, replication, fragmentation and allocation etc. This dissertationfocuses on database fragmentation and techniques which are useful for performingdatabase fragmentation. The objective of this research is to investigate efficient algorithm and technique fordatabase fragmentation in distributed environment. We proposed a customized ISUD(Insert, Select, Update, Delete) technique after comparative study of the best suitabletechniques, which is selected for implementation purpose. The functionality of thecustomized ISUD technique helps to get the precedence of the attribute of a relationhorizontally in database from various sites or location. The practical objective of this dissertation is to design the architecture and develop,implement customized ISUD (Insert, Select, Update, Delete) user interface, and to testthe selected algorithm or technique by using the interface. We used C#.Net as adevelopment tool. This user interface accepts ISUD frequency as an input andproduces ALP (attribute location precedence) values as output. We have incorporateddesign science research (DSR) method for customized ISUD technique development.This customized ISUD technique can be considered as a foundation to implementhorizontal database fragmentation in distributed environment, so that the databaseadministrator can take a proper decision for allocating the fragmented data to varioussites at initial state of distributed database design.
206

Active learning and compilation of higher order schema integration queries

Barbanson, François Gérard 28 August 2008 (has links)
Not available / text
207

Efficient query processing for spatial and temporal databases

Shou, Yutao, Sindy., 壽玉濤. January 2004 (has links)
published_or_final_version / abstract / toc / Computer Science and Information Systems / Master / Master of Philosophy
208

Impact of data modeling and database implementation methods on the optimization of conceptual aircraft design

Hall, Neil Scott 08 1900 (has links)
No description available.
209

Schema Integration : How to Integrate Static and Dynamic Database Schemata

Bellström, Peter January 2010 (has links)
Schema integration is the task of integrating several local schemata into one global database schema. It is a complex, error-prone and time consuming task. Problems arise in recognizing and resolving problems, such as differences and similarities, between two schemata. Problems also arise in integrating static and dynamic schemata. In this thesis, three research topics are addressed: Maintaining Vocabulary in Schema Integration, Integration of Static Schemata and Integration of Static and Dynamic Schemata, while applying the notation in the Enterprise Modeling approach. In Maintaining Vocabulary in Schema Integration an analysis of what semantic loss is and why it occurs in schema integration is conducted. Semantic loss is a problem that should be avoided because both concepts and dependencies might be lost. In the thesis, it is argued that concepts and dependencies should be retained as long as possible in the schemata. This should facilitate user involvement since the users’ vocabulary is retained even after resolving similarities and differences between two schemata. In Integration of Static Schemata two methods are developed. These methods facilitate recognition and resolution of similarities and differences between two conceptual database schemata.  By applying the first method, problems between two schemata can be recognized that otherwise could pass unnoticed; by applying the second method, problems can be resolved without causing semantic loss by retaining concepts and dependencies in the schemata. In Integration of Static and Dynamic Schemata a method on how to integrate static and dynamic schemata is developed. In the method, focus is put on pre- and post-conditions and how to map these to states and state changes in the database. By applying the method, states that are important for the database can be designed and integrated into the conceptual database schema. Also, by applying the method, active database rules can be designed and integrated into the conceptual database schema.
210

KeyX: selective key-oriented indexing in native XML-databases /

Hammerschmidt, Beda Christoph. January 2006 (has links)
Univ., Diss.--Lübeck, 2005. / Literaturverz. S. [165] - 175.

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