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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.
1181

Role-based Data Management

Jäkel, Tobias 29 May 2017 (has links) (PDF)
Database systems build an integral component of today’s software systems and as such they are the central point for storing and sharing a software system’s data while ensuring global data consistency at the same time. Introducing the primitives of roles and their accompanied metatype distinction in modeling and programming languages, results in a novel paradigm of designing, extending, and programming modern software systems. In detail, roles as modeling concept enable a separation of concerns within an entity. Along with its rigid core, an entity may acquire various roles in different contexts during its lifetime and thus, adapts its behavior and structure dynamically during runtime. Unfortunately, database systems, as important component and global consistency provider of such systems, do not keep pace with this trend. The absence of a metatype distinction, in terms of an entity’s separation of concerns, in the database system results in various problems for the software system in general, for the application developers, and finally for the database system itself. In case of relational database systems, these problems are concentrated under the term role-relational impedance mismatch. In particular, the whole software system is designed by using different semantics on various layers. In case of role-based software systems in combination with relational database systems this gap in semantics between applications and the database system increases dramatically. Consequently, the database system cannot directly represent the richer semantics of roles as well as the accompanied consistency constraints. These constraints have to be ensured by the applications and the database system loses its single point of truth characteristic in the software system. As the applications are in charge of guaranteeing global consistency, their development requires more effort in data management. Moreover, the software system’s data management is distributed over several layers, which results in an unstructured software system architecture. To overcome the role-relational impedance mismatch and bring the database system back in its rightful position as single point of truth in a software system, this thesis introduces the novel and tripartite RSQL approach. It combines a novel database model that represents the metatype distinction as first class citizen in a database system, an adapted query language on the database model’s basis, and finally a proper result representation. Precisely, RSQL’s logical database model introduces Dynamic Data Types, to directly represent the separation of concerns within an entity type on the schema level. On the instance level, the database model defines the notion of a Dynamic Tuple that combines an entity with the notion of roles and thus, allows for dynamic structure adaptations during runtime without changing an entity’s overall type. These definitions build the main data structures on which the database system operates. Moreover, formal operators connecting the query language statements with the database model data structures, complete the database model. The query language, as external database system interface, features an individual data definition, data manipulation, and data query language. Their statements directly represent the metatype distinction to address Dynamic Data Types and Dynamic Tuples, respectively. As a consequence of the novel data structures, the query processing of Dynamic Tuples is completely redesigned. As last piece for a complete database integration of a role-based notion and its accompanied metatype distinction, we specify the RSQL Result Net as result representation. It provides a novel result structure and features functionalities to navigate through query results. Finally, we evaluate all three RSQL components in comparison to a relational database system. This assessment clearly demonstrates the benefits of the roles concept’s full database integration.
1182

Nativní XML databáze s rozhraním XQuery / Native XML Database with XQuery Interface

Losert, Jakub Unknown Date (has links)
The aim of this Thesis is implement Aplication Programming Interface (API) with support of XML native documents. First part deal with introduction of XML model and with this markup language related technologies. Alfter that the thesis describe individual XML native databases solutions and focus to issues of persistence XML data stored in relational databases, analyse mapping methods applicable to their relational model. After that the thesis describe design and implementation of the API, which afford a resources for XML documents data holding and manipulating in relational database system. The final section of this thesis is assignment to aplication tests and evaluation of results.
1183

建構物件與物件關聯資料庫工作量產生器 / Toward a Generalized Object-Oriented and Object-Relational Database Workload Generator

黃敏男, Huang, Min-Nan Unknown Date (has links)
本研究以使用者需求導向為設計原則,提出了建構物件與物件關聯資料庫工作量產生器的發展方式,以解決(1)一般績效評估標準規格因只針對特定應用領域,而無法周詳考慮到使用者的特定需求問題;(2)廠商所發展的工作量產生器則因為可能針對其產品的特定領域作設計與測試,而失去了公正性之問題。我們的目地就是希望能以此資料庫工作量產生器的設計方式使測試資料庫效能的工作量,對使用者而言更具一致性、代表性與正確性,如此測試之結果對使用者而言才能更具意義。 我們首先分析SQL3與ODMG標準,以此構成物件關聯與物件導向資料庫之一般化的工作量模式。然後,再著手以使用者需求導向為原則,設計工作量產生器的運作方式。最後,我們實際發展了工作量產生器的雛形系統,以讓使用者能真正依其需求建立工作量並實際作績效測試,並提供給欲建構物件與物件關聯資料庫工作量產生器的人員作參考。 / This thesis provides a method of establishing Object-Oriented and Object-Relational Database Workload Generator, and this method is designed from the perspective of the user's requirements for addressing two problems: (1) the benchmark standards are generally designed to specific domains, so they are unable think comprehensively users' special requirements. (2) the database workload generators that developed by database providers may lose justice, because they might be designed to their products' special domain. Our purpose is that hope this method can make the Workload more consistent, more representative and more accurate and the test result will be more meaningful to users. Firstly, we analyze the SQL3 and ODMG standards to compose the ORDBs' and OODBs' generalized Workload Models. Then, we design our Workload Generator form the perspective of the user's requirements. Finally, we develop the Workload Generator's prototype system, it can allow users to create Workload according to their actual requirements and really do the benchmark test, and furthermore can provide a reference resource to the people who want to develop ORDB and OODB Workload Generator.
1184

分散式關聯資料庫系統績效評估工作量模式之研究 / Distributed RDBMS Benchmark Workload Modeling

韓先良, Han, Sien-Liang Unknown Date (has links)
本研究之主要目標在於建構一個能評估分散式關聯資料庫中之特色的需求導向績效評估方法。在過去的績效評估研究中,已經有許多人對於關聯式資料庫績效評估做了多方面的努力。但是,過去的關聯式資料庫資效評估方法如:Wisconsin、AS3AP、TPC系列的Benchmarks都有著一些限制及不足的地方。 過去的關聯式資料庫績效評估方法並無法完全的評估出分散式資料庫的特殊需求及其表現。所以本研究嘗試要建立出一個能專門適用於分散式資料庫導向的績效評估方法。為了要作出此績效評估方法,本研究採用了工作量模式的研究方法。先建出分散式資料庫績效評估的工作量模式,再以其來實作出績效評估方法。工作量模式分成三部分:資料模式、交易模式、控制模式。 / This thesis is intended to design a requirements-centric database benchmark, which can evaluate the general performance of the distributed relational database systems. In the past, there are many relational database benchmarks. But the relational database benchmarks like Wisconsin, AS3AP, TPC, TP1 have some constraints. In this study, we aim to design a general-purpose distributed database workload model and implement it. To design this benchmark, we need to build our workload model. The workload model consists of three components:data model, transaction model, control model. Each model has the requirement specification language to accommodate user's workloads.
1185

E-model: event-based graph data model theory and implementation

Kim, Pilho 06 July 2009 (has links)
The necessity of managing disparate data models is increasing within all IT areas. Emerging hybrid relational-XML systems are under development in this context to support both relational and XML data models. However, there are ever-growing needs for adequate data models for texts and multimedia, which are applications that require proper storage, and their capability to coexist and collaborate with other data models is as important as that of a relational-XML hybrid model. This work proposes a new data model named E-model that supports rich relations and reflects the dynamic nature of information. This E-model introduces abstract data typing objects and rules of relation that support: (1) the notion of time in object definition and relation, (2) multiple-type relations, (3) complex schema modeling methods using a relational directed acyclic graph, and (4) interoperation with popular data models. To implement the E-model prototype, extensive data operation APIs have been developed on top of relational databases. In processing dynamic queries, our prototype achieves an order of magnitude improvement in speed compared with popular data models. Based on extensive E-model APIs, a new language named EML is proposed. EML extends the SQL-89 standard with various E-model features: (1) unstructured queries, (2) unified object namespaces, (3) temporal queries, (4) ranking orders, (5) path queries, and (6) semantic expansions. The E-model system can interoperate with popular data models with its rich relations and flexible structure to support complex data models. It can act as a stand-alone database server or it can also provide materialized views for interoperation with other data models. It can also co-exist with established database systems as a centralized online archive or as a proxy database server. The current E-model prototype system was implemented on top of a relational database. This allows significant benefits from established database engines in application development. In addition to extensive features added to SQL, our EML prototype achieves an order of magnitude speed improvement in dynamic queries compared to popular database models. Availability Release the entire work immediately for access worldwide after my graduation.
1186

The design of a database of resources for rational therapy

Steyn, Genevieve Lee 06 1900 (has links)
The purpose of this study is to design a database of resources for rational therapy. An investigation of the current health situation and reorientation towards primary health care (PHC) in South Africa evidenced the need for a database of resources which would meet the demand for rational therapy information made on the Helderberg College Library by various user groups as well as make a contribution to the national health information infrastructure. Rational therapy is viewed as an approach within PHC that is rational, common-sense, wholistic and credible, focusing on the prevention and maintenance of health. A model of the steps in database design was developed. A user study identified users' requirements for design and the conceptual schema was developed. The entities, attributes, relationships and policies were presented and graphically summarised in an Entity-Relationship (E-R) diagram. The conceptual schema is the blueprint for further design and implementation of the database. / Information Science / M.Inf.
1187

Rozhraní pro aspektové vyhledávání v indexu Wikipedie / Interfaces for Faceted Search in Indexed Wikipedia

Cilip, Peter January 2018 (has links)
Main aim of this thesis is to study existing systems of faceted search and to design own system based on faceted search in the index of Wikipedia. In this thesis we can meet with existing solutions of faceted search. From mistakes and failures of existing solutions was designed our own system, that is output of this thesis. Designed system is described in way of design and implementation. Product of thesis is application and graphical interface. Application interface can be integrated into existing informational system, where it can be used as multidimensional filter. Graphical interface provides option how can application interface be used in real system. System was created focusing on usefullness and simplicity, for using in existing information systems.
1188

Migrace systémové databáze elektronického obchodu / E-commerce System Database Migration

Zkoumalová, Barbora January 2016 (has links)
The object of master‘s thesis is design and creation of e-commerce system database migration tool from the ZenCart platform to the PrestaShop platform. Both system databases will be described and analysed and based on gained information the migration tool will be created according customers‘ requirements and then final data migration from original to the new database will be executed.
1189

Role-based Data Management

Jäkel, Tobias 24 March 2017 (has links)
Database systems build an integral component of today’s software systems and as such they are the central point for storing and sharing a software system’s data while ensuring global data consistency at the same time. Introducing the primitives of roles and their accompanied metatype distinction in modeling and programming languages, results in a novel paradigm of designing, extending, and programming modern software systems. In detail, roles as modeling concept enable a separation of concerns within an entity. Along with its rigid core, an entity may acquire various roles in different contexts during its lifetime and thus, adapts its behavior and structure dynamically during runtime. Unfortunately, database systems, as important component and global consistency provider of such systems, do not keep pace with this trend. The absence of a metatype distinction, in terms of an entity’s separation of concerns, in the database system results in various problems for the software system in general, for the application developers, and finally for the database system itself. In case of relational database systems, these problems are concentrated under the term role-relational impedance mismatch. In particular, the whole software system is designed by using different semantics on various layers. In case of role-based software systems in combination with relational database systems this gap in semantics between applications and the database system increases dramatically. Consequently, the database system cannot directly represent the richer semantics of roles as well as the accompanied consistency constraints. These constraints have to be ensured by the applications and the database system loses its single point of truth characteristic in the software system. As the applications are in charge of guaranteeing global consistency, their development requires more effort in data management. Moreover, the software system’s data management is distributed over several layers, which results in an unstructured software system architecture. To overcome the role-relational impedance mismatch and bring the database system back in its rightful position as single point of truth in a software system, this thesis introduces the novel and tripartite RSQL approach. It combines a novel database model that represents the metatype distinction as first class citizen in a database system, an adapted query language on the database model’s basis, and finally a proper result representation. Precisely, RSQL’s logical database model introduces Dynamic Data Types, to directly represent the separation of concerns within an entity type on the schema level. On the instance level, the database model defines the notion of a Dynamic Tuple that combines an entity with the notion of roles and thus, allows for dynamic structure adaptations during runtime without changing an entity’s overall type. These definitions build the main data structures on which the database system operates. Moreover, formal operators connecting the query language statements with the database model data structures, complete the database model. The query language, as external database system interface, features an individual data definition, data manipulation, and data query language. Their statements directly represent the metatype distinction to address Dynamic Data Types and Dynamic Tuples, respectively. As a consequence of the novel data structures, the query processing of Dynamic Tuples is completely redesigned. As last piece for a complete database integration of a role-based notion and its accompanied metatype distinction, we specify the RSQL Result Net as result representation. It provides a novel result structure and features functionalities to navigate through query results. Finally, we evaluate all three RSQL components in comparison to a relational database system. This assessment clearly demonstrates the benefits of the roles concept’s full database integration.
1190

Analýza a optimalizace databázových systémů / Database System Analysis and Implementation

Třetina, Jan January 2008 (has links)
With the increase of demands for the speed and availability of the information technologies, the process of optimization gains more and more importance. Concerning search engine optimization, optimization of operating systems or application optimization (source code), the goal is to gain faster, smaller and more maintainable solution. In my thesis I deal with optimization of database systems, which includes low level of database tuning - physical organization of data and indices, database management system tuning and query optimization. I focused on optimization of Microsoft SQL Servers 2005 in enterprise environment.

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