Design and development of databases

MINISTRY OF EDUCATION AND SCIENCE

OF THE REPUBLIC OF KAZAKHSTAN

South Kazakhstan State University named after M.O. Auezov

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CASE

Theme: Design and development of databases

Prepared by: Usen M.M

Group: UM18-4K

Accepted:Bibulova D.A.

Shymkent-2019y

Table of contents

1.Introduction

2.Main part

         2.1.Database design

         2.2.Normalization of relarions

         3.Conclusion

          4. References

Introduction

        In recent years, a new industry has come to the fore - the information industry, associated with the production of technical means, methods and technologies for the production of new knowledge. This industry is closely related to the development of computer technology.

The whole way of life, the system of values ​​will change: the importance of cultural leisure is increasing, the demand for knowledge is increasing, the ability of intellectual work and creativity is required of a person.
As a result, there appeared contradictions between the limited human abilities in perception and processing of information and the existing arrays of stored and transmitted information. There is a large number of redundant information, in which it is sometimes difficult to navigate and select the necessary information. Automated databases are used to solve such problems. They have become an integral part of almost all computer systems - from the industry to a separate enterprise.

    Relational DBMS (Database Management System) - DBMS that manages relational databases. The notion of relational (eng. Relatio - relation) is connected with the development of the famous English specialist in the field of database systems Edgar Codd.

These models are characterized by simplicity of the data structure, user-friendly tabular presentation and the possibility of using the formal apparatus of relation algebra and relational calculus for data processing.

Database design

Designing and creating a database that could fully meet customer needs, was convenient and easy to use, did not create problems and anomalies during the operation of the system, and requires a serious understanding of all aspects of the database life cycle. Anyone who plans to create and implement a database will have to think about a qualified approach to both the design of the database and its operation.

     Designing is considered to be the most important stage in creating a database, since it is at this stage that all the most important features of the database work are laid. Moreover, today databases are rarely used by themselves and, as a rule, are a component of a certain information system. The above defines an important point - before designing the database itself, choosing a design methodology, you will need to determine, design and take into account further data usage algorithms, that is, in essence, database functionality not limited solely to information storage.

    Given the above, the design and creation of a database are carried out at the levels:

1. concepts (definition of data requirements) with obtaining a conceptual database model;

2. logic (converting requirements into a data structure) with obtaining a DBMS-oriented database 3. structure and application software specifications, often in several variants with reference to 4. 4. different DBMS;

5. physical design.

    Designing and creating a database differs from other applications in the necessity of professional implementation, configuration and maintenance. Simple solutions usually do not require the involvement of specialists for ongoing service, but in any case it is necessary to study at least the basics of working in a particular software environment. Complex information systems in operation are extremely dependent on the appropriate level of methodological and technical support.

Physical design

Physical database design - this is the process of preparing a description of the implementation of the database on the secondary storage devices; This step examines the main relationships, the organization of files and indices designed to ensure effective access to data, and related integrity limitations and protection tools. When starting a physical design of the database, it is first of all necessary to select a specific target DBMS. Therefore, the physical design of the explosion is connected with a specific DBMS.

Inter-physical physical design there is a constant feedback, as well as decisions taken at the stage of physical design with the aim of increasing the productivity of the system, capable of influencing the structure of the logical model. As a rule, the main purpose of the physical database design is the description of the physical implementation of the logical project database.

Normalization of relations

 Normalization is the division of the tables over the edges or more, with the best properties of the inclusion, change and removal. The final normalization procedure is made for obtaining the project data, in which each fact occurs only in the water space, i.e. Excess of information is excluded. This is a good way to save memory, because it is possible to eliminate the possibility of contradicting stored data. The data management system for specifying links in the table is responsible for their linking operations. Consider the most frequent binary links: