The use of modeling tools at the stages of database design

Abstract

The article discusses the possibilities of using modeling tools at the stages of database design. Database design is one of the most complex and crucial tasks associated with the creation of an automated information system. As a result of solving this problem, the content of the database should be determined, an effective way for organizing data for all its future users, and data management tools. The main goal of this stage is to develop such a database scheme that it includes the necessary and sufficient data on information objects, their properties and relationships in accordance with the objects of the subject area and the processes of their transformation. The authors present the results of using modeling tools to solve the problems of the database design stage. Creating models is considered from the point of view of three-circuit architecture, the main principle of which is abstraction. To display the levels of data presentation, three related models have been developed: an external data model that displays the representations of each type of user existing in the organization (description of the subject area); a conceptual data model that displays a logical (or generalized) idea of data, independent of the type of database management system selected; an internal data model that displays the conceptual diagram in a specific way that is understandable to the selected target database management system. As an example of a subject area, the activity of a school of foreign languages is considered, namely, the registration of students in a school. The main problem is the large amount of information that is processed manually: paper forms of clients are drawn up, reports on the implementation of work are manually generated and filled out. It is necessary to develop a draft database for the registration of students of a school of foreign languages and to further implement it in the environment of the selected database management system.