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1 – 10 of over 13000Nikitas N. Karanikolas and Michael Vassilakopoulos
The purpose of this paper is to compare the use of two Object-Relational models against the use of a post-Relational model for a realistic application. Although real-world…
Abstract
Purpose
The purpose of this paper is to compare the use of two Object-Relational models against the use of a post-Relational model for a realistic application. Although real-world applications, in most cases, can be adequately modeled by the Entity-Relationship (ER) model, the transformation to the popular Relational model alters the representation of structures common in reality, like multi-valued and composite fields. Alternative database models have been developed to overcome these shortcomings.
Design/methodology/approach
Based on the ER model of a medical application, this paper compares the information representation, manipulation and enforcement of integrity constraints through PostgreSQL and Oracle, against the use of a post-Relational model composed of the Conceptual Universal Database Language (CUDL) and the Conceptual Universal Database Language Abstraction Level (CAL).
Findings
The CAL/CUDL pair, although more periphrastic for data definition, is simpler for data insertions, does not require the use of procedural code for data updates, produces clearer output for retrieval of attributes, can accomplish retrieval of rows based on conditions that address composite data with declarative statements and supports data validation for relationships between composite data without the need for procedural code.
Research limitations/implications
To verify, in practice, the conclusions of the paper, complete implementation of a CAL/CUDL system is needed.
Practical implications
The use of the CAL/CUDL pair would advance the productivity of database application development.
Originality/value
This paper highlights the properties of realistic database-applications modelling and management that are desirable by developers and shows that these properties are better satisfied by the CAL/CUDL pair.
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A survey of current work on database systems is presented. The area is divided into three main sectors: data models, data languages and support for database operations. Data…
Abstract
A survey of current work on database systems is presented. The area is divided into three main sectors: data models, data languages and support for database operations. Data models are presented as the link between the database and the real world. Languages range from formal algebraic languages to attempts to use a dialogue in English to formulate queries. The support includes hardware for content addressing, database machines and software techniques for optimizing and evaluating group expressions. Mathematical models are used to organize this support. Throughout there is a tutorial component and evaluation, which in both cases is related to the application of database ideas to documentation.
Bijoy Bordoloi, Atul Agarwal and Sumit Sircar
The relational model and relational database management systems havebeen the de facto industry standard for organizing and managing data inmost computer‐integrated manufacturing…
Abstract
The relational model and relational database management systems have been the de facto industry standard for organizing and managing data in most computer‐integrated manufacturing environments. In recent years, however, some new database technologies have emerged – namely, object‐oriented and hybrid or extended relational – making the job of the CIM managers more difficult with regard to selecting a database technology that would be most appropriate for their operations. Presents a framework for selecting an appropriate DBMS type in a CIM setting depending on a company′s ENTITY and DATA needs. It is hoped that the presented framework would prove useful to practising managers.
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The five principal management objectives of database management systems are discussed, as are the four basic criteria for comparing systems. Database management systems organized…
Abstract
The five principal management objectives of database management systems are discussed, as are the four basic criteria for comparing systems. Database management systems organized along hierarchies and networks are illustrated and compared to relational database systems, which are also illustrated. Backend processors, emphasizing database machines, are described as important means of improving database management system performance and of exploiting the potential of relational databases in particular.
Byron J. Dangerfield and John S. Morris
In this article the properties of relational database managementsystems (DBMSs) are discussed. It is shown how they can be used as aneffective tool for performing the function of…
Abstract
In this article the properties of relational database management systems (DBMSs) are discussed. It is shown how they can be used as an effective tool for performing the function of primary‐key‐coding schemes for classifying product families in the application of group technology. The attributes of the relational DBMS are demonstrated and compared to traditional coding schemes.
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A workstation‐based system for materials planning is intended tocomplement a host‐based materials‐planning system, thereby leading to amulti‐level system that combines fully…
Abstract
A workstation‐based system for materials planning is intended to complement a host‐based materials‐planning system, thereby leading to a multi‐level system that combines fully detailed planning procedures with “aggregate” decision support capabilities. Planning objects as well as planning procedures are formulated within the relational database frame‐work. By that means, at execution time the database management system guarantees processing efficiency as well as consistency control. After a short characterisation of the state‐of‐the‐art of database utilisation in conventional materials planning, a set of requirements which have to be met by the proposed approach is formulated. Based on this, the suitability of the relational database model as a framework for multi‐stage materials planning is discussed. In particular, the integration of abstraction hierarchies is emphasised and hierarchical planning procedures adopted from artificial intelligence are integrated into the concept. Some examples adopted from a prototype show that, at least for simple planning problems, it is possible to achieve end‐user support at any level of detail when using a relational database system for materials planning.
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Aya Khaled Youssef Sayed Mohamed, Dagmar Auer, Daniel Hofer and Josef Küng
Data protection requirements heavily increased due to the rising awareness of data security, legal requirements and technological developments. Today, NoSQL databases are…
Abstract
Purpose
Data protection requirements heavily increased due to the rising awareness of data security, legal requirements and technological developments. Today, NoSQL databases are increasingly used in security-critical domains. Current survey works on databases and data security only consider authorization and access control in a very general way and do not regard most of today’s sophisticated requirements. Accordingly, the purpose of this paper is to discuss authorization and access control for relational and NoSQL database models in detail with respect to requirements and current state of the art.
Design/methodology/approach
This paper follows a systematic literature review approach to study authorization and access control for different database models. Starting with a research on survey works on authorization and access control in databases, the study continues with the identification and definition of advanced authorization and access control requirements, which are generally applicable to any database model. This paper then discusses and compares current database models based on these requirements.
Findings
As no survey works consider requirements for authorization and access control in different database models so far, the authors define their requirements. Furthermore, the authors discuss the current state of the art for the relational, key-value, column-oriented, document-based and graph database models in comparison to the defined requirements.
Originality/value
This paper focuses on authorization and access control for various database models, not concrete products. This paper identifies today’s sophisticated – yet general – requirements from the literature and compares them with research results and access control features of current products for the relational and NoSQL database models.
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Subhashish Samaddar and Arun Rai
At the heart of successful automated manufacturing systems lies theidea of effective integration of various functions. In any sizeableapplication of a Computer Integrated…
Abstract
At the heart of successful automated manufacturing systems lies the idea of effective integration of various functions. In any sizeable application of a Computer Integrated Manufacturing (CIM) system, an enormous amount of complex data needs to be logically integrated and managed. Presents and discusses the complex nature of CIM data and the difficulties associated with managing them. Given these difficulties, effective data management of such advanced manufacturing systems poses a challenging task for system designers and managers. Given the growing rate of diffusion of relational databases, it is important to explore the capabilities of this technology in serving the data management needs of manufacturing systems. Proposes a relational database schema, as opposed to a hierarchical or a network model. Uses appropriate examples from a Cellular Manufacturing setting to illustrate the proposed schema. Discusses issues related to distributing and logically integrating databases, and outlines managerial implications associated with rapidly changing information management technologies.
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Marilyn Lutz and Curtis Meadow
To describe the evolution of a content management system at the University of Maine Library that would function as a universal, extensible metadata repository, thereby eliminating…
Abstract
Purpose
To describe the evolution of a content management system at the University of Maine Library that would function as a universal, extensible metadata repository, thereby eliminating the need to build separate databases for new digital collections, and facilitating both end‐user access and the management of electronic resources in an integrated technology environment.
Design/methodology/approach
Beginning with the development of a prototype system that mapped EAD encoded finding aids to a relational database, this paper discusses the evolution of this prototype into the design and implementation of a RDBMS (and continuing development of an object‐oriented database management systems (OODBMS) system) to actively manage digital objects and associated metadata. The key to the system design is metadata: extracting and mapping, transforming, and managing the processing of MARC‐based metadata into non‐MARC schemes to build digital collections. Other relevant CMS architecture issues discussed are the design of a functional bibliographic structure and utilities for metadata harvesting and indexing.
Findings
Provides information on the use of the Dublin Core Abstract Model and a flexible and adaptable collection‐centric approach in the overall CMS architecture as implemented on a non‐MARC RDBMS, and provides an explanation of the advantages of an object oriented database system over the complexity of evolving relational database tables.
Practical implications
A useful source for the development of an in‐house CMS, and a contribution to the growing body of literature about the transformation of MARC‐based metadata for database design.
Originality/value
This paper is a case study of actual work conducted at the University of Maine Library. The RDBMS manages digital collections; the OODBMS manages digital video and other multimedia resources.
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As manufacturing systems change from island of automation to enterprise‐wise integration, object‐oriented database and database management systems have many superior features to…
Abstract
As manufacturing systems change from island of automation to enterprise‐wise integration, object‐oriented database and database management systems have many superior features to meet the new requirements. Based on the comparison with relational databases, this paper discusses the selections and characteristics of the object‐oriented database and database management systems (OODBMS) in manufacturing and summarizes the current studies and applications. It helps managers to choose appropriate OODBMS products based on the degree of complexity of their firm’s entity and data items. It provides a direction for future research.
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