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1 – 2 of 2Nikitas 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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Vassilis Kostoglou, Michael Vassilakopoulos and Christos Koilias
The purpose of this paper is to focus on a thorough comparison of the broader specialties and subspecialties provided by Greek higher technological education, regarding the…
Abstract
Purpose
The purpose of this paper is to focus on a thorough comparison of the broader specialties and subspecialties provided by Greek higher technological education, regarding the employment status and the vocational prospects of the corresponding graduates, and aims to identify and analyze the relevant existing differences.
Design/methodology/approach
Original empirical data were collected from 5,183 graduates of Technological Educational Institutes of higher education through a national survey using telephone interviews and a structured questionnaire. The stratified sample consisted of graduates originating from all nine different broader specialties (faculties) and 45 subspecialties (departments). Descriptive, bivariate and multivariate statistical analysis was used for the elaboration of the collected information.
Findings
The results showed that there are significant differences among the graduates of different specialties regarding some employment characteristics, such as professional status, type of employment, relevance between present work and Bachelor studies, and satisfaction from employment and wages. Additionally, the results identify distinguished clusters among certain broader specialties and subspecialties regarding graduates’ employment status and characteristics.
Practical implications
The revealed existence of strong relationships between broader specialties/subspecialties and their graduates’ vocational prospects can offer justified advice/guidelines to secondary education graduates for applying to specialties presenting promising employment prospects.
Originality/value
This work, being one of the very few nation‐wide studies, reveals and highlights the most important higher education specialties regarding the vocational status and prospects of the corresponding graduates, providing a guideline for the selection of the subject of studies that leads to a more promising career.
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