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Open Access
Article
Publication date: 9 October 2023

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…

1035

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.

Details

International Journal of Web Information Systems, vol. 20 no. 1
Type: Research Article
ISSN: 1744-0084

Keywords

Article
Publication date: 1 September 2005

Z.M. Ma

To provide a selective bibliography for researchers and practitioners interested in database modeling of engineering information with sources which can help them develop…

1948

Abstract

Purpose

To provide a selective bibliography for researchers and practitioners interested in database modeling of engineering information with sources which can help them develop engineering information systems.

Design/methodology/approach

Identifies the requirements for engineering information modeling and then investigates how current database models satisfy these requirements at two levels: conceptual data models and logical database models.

Findings

Presents the relationships among the conceptual data models and the logical database models for engineering information modeling viewed from database conceptual design.

Originality/value

Currently few papers provide comprehensive discussions about how current engineering information modeling can be supported by database technologies. This paper fills this gap. The contribution of the paper is to identify the direction of database study viewed from engineering applications and provide a guidance of information modeling for engineering design, manufacturing, and production management.

Details

Industrial Management & Data Systems, vol. 105 no. 7
Type: Research Article
ISSN: 0263-5577

Keywords

Article
Publication date: 4 November 2014

Nikitas 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.

Details

Journal of Systems and Information Technology, vol. 16 no. 4
Type: Research Article
ISSN: 1328-7265

Keywords

Article
Publication date: 13 November 2009

Yaojun Han, Changjun Jiang and Xuemei Luo

The purpose of this paper is to present a scheduling model, scheduling algorithms, and formal model and analysis techniques for concurrency transaction in grid database

Abstract

Purpose

The purpose of this paper is to present a scheduling model, scheduling algorithms, and formal model and analysis techniques for concurrency transaction in grid database environment.

Design/methodology/approach

Classical transaction models and scheduling algorithms developed for homogeneous distributed architecture will not work in the grid architecture and should be revisited for this new and evolving architecture. The conventional model is improved by three‐level transaction scheduling model and the scheduling algorithms for concurrency transaction is improved by considering transmission time of a transaction, user's priority, and the number of database sites accessed by the transaction as a priority of the transaction. Aiming at the problems of analysis and modeling of the transaction scheduling in grid database, colored dynamic time Petri nets (CDTPN) model are proposed. Then the reachability of the transaction scheduling model is analyzed.

Findings

The three‐level transaction scheduling model not only supports the autonomy of grid but also lightens the pressure of communication. Compared with classical transaction scheduling algorithms, the algorithms not only support the correctness of the data but also improve the effectiveness of the system. The CDTPN model is convenient for modeling and analyzing dynamic performance of grid transaction. Some important results such as abort‐ratio and turnover‐time are gotten by analyzing reachability of CDTPN.

Originality/value

The three‐level transaction scheduling model and improved scheduling algorithms with more complex priority are presented in the paper. The paper gives a CDTPN model for modeling transaction scheduling in grid database. In CDTPN model, the time interval of a transition is a function of tokens in input places of the transition.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 28 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 January 1979

MALCOLM P. ATKINSON

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

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.

Details

Journal of Documentation, vol. 35 no. 1
Type: Research Article
ISSN: 0022-0418

Article
Publication date: 1 April 2003

Heng‐Li Yang

This research conducted two experiments to understand the performance (correctness and efficiency) of novice database designers, and perceptions of ease of use and preferences of…

6349

Abstract

This research conducted two experiments to understand the performance (correctness and efficiency) of novice database designers, and perceptions of ease of use and preferences of two approaches for modeling relational databases: the semantic‐oriented approach (top‐down, e.g. using the entity‐relationship model) and the logical‐oriented approach (bottom‐up, view decomposition, focusing only on the logical model). The findings indicated that in experiment 1, semantic‐oriented treatments performed better in a complex, written‐text case; logical‐oriented treatments were better in a simple, tabular‐form case. The same situation happened in experiment 2 though the differences were not statistically significant.

Details

Industrial Management & Data Systems, vol. 103 no. 3
Type: Research Article
ISSN: 0263-5577

Keywords

Article
Publication date: 1 December 1994

Gerti Kappel and Stefan Vieweg

Changes in market and production profiles require a more flexibleconcept in manufacturing. Computer integrated manufacturing (CIM)describes an integrative concept for joining…

1393

Abstract

Changes in market and production profiles require a more flexible concept in manufacturing. Computer integrated manufacturing (CIM) describes an integrative concept for joining business and manufacturing islands. In this context, database technology is the key technology for implementing the CIM philosophy. However, CIM applications are more complex and thus more demanding than traditional database applications such as business and administrative applications. Systematically analyses the database requirements for CIM applications including business and manufacturing tasks. Special emphasis is given on integration requirements due to the distributed, partly isolated nature of CIM applications developed over the years. An illustrative sampling of current efforts in the database community to meet the challenge of non‐standard applications such as CIM is presented.

Details

Integrated Manufacturing Systems, vol. 5 no. 4/5
Type: Research Article
ISSN: 0957-6061

Keywords

Article
Publication date: 1 January 1989

EMMANUEL J. YANNAKOUDAKIS and HUSSAIN A. ATTAR‐BASHI

The Subject‐Object Relationship Interface model (SORI) described in this paper is a novel approach that displays many of the structures necessary to map between the conceptual…

107

Abstract

The Subject‐Object Relationship Interface model (SORI) described in this paper is a novel approach that displays many of the structures necessary to map between the conceptual level and the external level in a database management system, which is an information‐oriented view of data. The model embodies a semantic synthesiser, which is based on an algorithm that maps the syntactic representation of a tuple or a record onto a semantic representation. This is based on table‐driven semantics which are embedded in the database model. The paper introduces a technique for translating tuples into natural language sentences, and discusses a system that has been fully implemented in PROLOG.

Details

Journal of Documentation, vol. 45 no. 1
Type: Research Article
ISSN: 0022-0418

Article
Publication date: 1 February 1993

Umberto Cavallaro, Paolo Paolini, Stavros Christodoulakis, Costis Dallas, Andreas Enotiadis, Saverio Proia, Jack Schiff and Wolfgang Schuler

HIFI (ESPRIT Project 6532) creates a set of tools to allow a reader to access a large body of heterogeneous information, managed by external databases created beforehand, through…

Abstract

HIFI (ESPRIT Project 6532) creates a set of tools to allow a reader to access a large body of heterogeneous information, managed by external databases created beforehand, through a hypertext interface. Information currently found in information systems is based on different media and is usually managed by different tools, like relational databases and a variety of multimedia database systems. Sometimes the need arises to ‘browse’ through the information using an interactive and intuitive interface. Hypertext is probably the best current means for interactive (and possibly intuitive) navigation through a heterogeneous body of information. Available hypertext tools, however, are usually seen as being for managing their own information rather than being an interface for accessing external databases. The HIFI approach is based on a model‐based description of the hypertext application, as it appears to the reader. A declarative and/or operational mapping translates hypertext operations (search, queries and navigation) into operations on the underlying information base and also ‘materialises’ hypertext objects, using objects of the underlying databases. The system also implements methodologies to support the hypertext interface development process. Real‐life applications will be developed to show the validity of the approach, with the cooperation of important end‐users who will cooperate with the project directly, either as partners or sponsors.

Details

The Electronic Library, vol. 11 no. 2
Type: Research Article
ISSN: 0264-0473

Article
Publication date: 1 March 2006

Yanjun Zuo and Brajendra Panda

Damage assessment and recovery play key roles in the process of secure and reliable computer systems development. Post‐attack assessment in a distributed database system is rather…

Abstract

Purpose

Damage assessment and recovery play key roles in the process of secure and reliable computer systems development. Post‐attack assessment in a distributed database system is rather complicated due to the indirect dependencies among sub‐transactions executed at different sites. Hence, the damage assessment procedure in these systems must be carried out in a collaborative way among all the participating sites in order to accurately detect all affected data items. This paper seeks to propose two approaches for achieving this, namely, centralized and peer‐to‐peer damage assessment models.

Design/methodology/approach

Each of the two proposed methods should be applied immediately after an intrusion on a distributed database system was reported. In the category of the centralized model, three sub‐models are further discussed, each of which is best suitable for a certain type of situations in a distributed database system.

Findings

Advantages and disadvantages of the models are analyzed on a comparative basis and the most suitable situations to which each model should apply are presented. A set of algorithms is developed to formally describe the damage assessment procedure for each model (sub‐model). Synchronization is essential in any system where multiple processes run concurrently. User‐level synchronization mechanisms have been presented to ensure that the damage assessment operations are conducted in a correct order.

Originality/value

The paper proposes two means for damage assessment.

Details

Information Management & Computer Security, vol. 14 no. 2
Type: Research Article
ISSN: 0968-5227

Keywords

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