Wyniki wyszukiwania - BazTech

1

Model for dynamic and hierarchical data repository in relational database

Piech M., Fracz W., Turek W., Kisiel-Dorohinicki M., Dajda J., Byrski A.

Computer Science

|

2018

|

Vol. 19 (4)

479--500

EN

The aim of this research is to build an open schema model for a digital sources repository in a relational database. This required us to develop a few advanced techniques. One of them was to keep and maintain a hierarchical data structure pushed into the repository. A second was to create constraints on any hierarchical level that allows for the enforcement of data integrity and consistency. The created solution is mainly based on a JSON file as a native column type, which was designed for holding open schema documents. In this paper, we present a model for any repository that uses hierarchical dynamic data. Additionally, we include a structure for normalizing the input and description for the data in order to keep all of the model assumptions. We compared our solution with a well-known open schema model – Entity-Attribute-Value – in the scope of saving data and querying about relationships and contents from the structure. The results show that we achieved improvements in both the performance and disk space usage, as we extended our model with a few new features that the previous model does not include. The techniques developed in this research can be applied in every domain where hierarchical dynamic data is required, as demonstrated by the digital book repository that we have presented.

2

A new approach to storing dynamic data in relational databases using JSON

Piech M., Marcjan R.

Computer Science

|

2018

|

Vol. 19 (1)

5--22

EN

JavaScript Object Notation was originally designed to transfer data; however, it soon found another use as a way to persist data in NoSQL databases. Recently, the most popular relational databases introduced JSON as native column type, which makes it easier to store and query dynamic database schema. In this paper, we review the currently popular techniques of storing data with a dynamic model with a large number of relationships between entities in relational databases. We focus on creating a simple dynamic schema with JSON in the most popular relational databases and we compare it with well-known EAV/CR data model and the document database. The results of precisely selected tests in the field of Criminal Data suggest that the use of JSON in dynamic database schema greatly simplifies queries and reduces their execution time compared to widely used approaches.

3

HEARTFAID's eCRF: Lessons learnt from using a two-level data acquisition and storage system for knowledge discovery tasks within an electronic platform for managing heart failure patients

Kononowicz A. A., Styczkiewicz K., Bacior B., Bošnjak M., Horvat R., Prcela M., Gamberger D., Sciacqua A., Valentini M. C., Kawecka-Jaszcz K., Parati G., Conforti D.

Bio-Algorithms and Med-Systems

|

2009

|

Vol. 5, no. 10

59--69

EN

Case report forms are important sources of medical knowledge in all clinical studies. Electronic versions of these forms have several advantages compared to traditional paper-based questionnaires, and they have been adopted in many contemporary research projects in medicine. This paper presents a framework for creating case report forms designed with a two-level approach. Data at the generic information model level is stored in EAV (entity-attribute-value) tables and extended by tables facilitating specification of the questionnaire layout. The second layer (knowledge model) specifies the domain specific concepts describing the field of application of the questionnaire. This framework has been applied and tested in the frame of an EU FP6 research project - HEARTFAID - the objective of which was to build a knowledge-based platform supporting the management of elderly patients suffering from heart failure. Data collected by the electronic case report form (eCRF) was used in the project's knowledge discovery and decision support tasks. The work presents a new way for effective extraction of the data necessary for the integration with the knowledge discovery process in a distributed, service oriented framework of the HEARTFAID platform. It is demonstrated that it is feasible to implement these tasks using the two-level EAV table design.

4

Modelowanie typu Entity-Attribute-Value w bazach danych

Gramacki A., Gramacki J.

Pomiary Automatyka Kontrola

|

2007

|

R. 53, nr 5

54-55

PL

W artykule omówiono pewien specyficzny sposób reprezentacji danych, który w pewnych sytuacjach może być stosowany w miejsce klasycznego podejścia relacyjnego. Jest on stosunkowo mało znany i choć zakres jego stosowalności jest ograniczony a pewne niekorzystne właściwości znaczne, to warto go poznać, gdyż istnieją obszary, gdzie jego stosowanie może przynieść wymierne korzyści. Mowa tu o tzw. podejściu Entity-Attribute-Value, w skrócie EAV. Jest ono całkowicie różne od podejścia relacyjnego. W pracy pokazano główne założenia EAV wraz z przykładami oraz omówiono jego podstawowe zalety i wady. Krótko omówiono również pewne alternatywne rozwiązanie do EAV, które posiada niektóre cechy EAV, a jednocześnie nie burzy tak bardzo podejścia relacyjnego.

EN

In the paper a specific kind of data representation is presented. In some situations it can be used in place of classical relational approach. This data representation, although not new, is not widely known, and in spite of some serious limitations, can be used in many specific database areas. We describe the Entity-Attribute-Value (EAV) approach. This approach is totally different to the relational one. In the paper we give an overview of the EAV as well as we show the main advantages and disadvantages. Also, we show an alternative approach to EAV which does not suffer the EAV limitations.