Information Storage And Management System

1373 Words6 Pages
Introduction With the development of technology, information storage and management have been vital of importance. Information effectiveness and efficiency are determined by how well data is organised and processed. The term ‘data’ have been widely employed in different human activities, including science, business, education, law and the like. Here, data is a means for representation of facts, concepts, and instructions in order to communicate (Sumathi & Esakkirajan 2007). Nevertheless, if data management is ineffective, and relevant information cannot be found quickly, a large amount data will become a liability rather than an asset of an organisation; thus, tools used for data management give rise to the occurrence of database…show more content…
6). This literature review will consist of four parts. Firstly, it will briefly introduce DBMSs and review the development of data models. Secondly, it will discuss DBMS products based on the relational data model. Following that, DBMS products based on logical models will be illustrated. Lastly, strengths and weaknesses between different data models will be demonstrated. 1. Overview of DBMSs and the development of data models 1.1 Overview of DBMSs A DBMS contains four parts, the data model, the data definition language (DDL), the data manipulation language (DML), and the data dictionary. To begin with, the data model describes how data are logically constructed. Next, programmers use DDL to specify the types of information and structure of the database, which is the important connection between the logical (how to perceive data) and physical views (how data are stored and processed) of the database. Thirdly, DML is used to manipulate the data, where end users or programmers are allowed to extract data in order to satisfy information requests and develop applications. Manipulative verbs are included in DML, such as ‘modify, delete or select’. In addition, the data dictionary is used for the storage of data elements and data characteristics, including ownership, physical representation, authorization, and security (technology guide). The use of a DBMS
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