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Introduction to DataBase Management System (DBMS), A database management system (DBMS) refers to the technology for creating and managing, databases. DBMS is a software tool to organize (create, retrieve, update, and manage) data in a, database., The main aim of a DBMS is to supply a way to store up and retrieve database information that is, both convenient and efficient. By data, we mean known facts that can be recorded and that have, embedded meaning. Usually, people use software such as DBASE IV or V, Microsoft ACCESS,, or EXCEL to store data in the form of a database. A datum is a unit of data. Meaningful data, combined to form information. Hence, information is interpreted data - data provided with, semantics. MS. ACCESS is one of the most common examples of database management, software., , Advantages of DBMS:, , , Data independence: Application programs should be as free or independent as possible from, details of data representation and storage. DBMS can supply an abstract view of the data for, insulating application code from such facts., , , , Efficient data access: DBMS utilizes a mixture of sophisticated concepts and techniques for, storing and retrieving data competently. This feature becomes important in cases where the data, is stored on external storage devices., , , , Data integrity and security: If data is accessed through the DBMS, the DBMS can enforce, integrity constraints on the data., , , , Data administration: When several users share the data, integrating the administration of data, can offer significant improvements. Experienced professionals understand the nature of the data, being managed and can be responsible for organizing the data representation to reduce, redundancy and make the data to retrieve efficiently.

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Components of DBMS:, , , , Users: Users may be of any kind such as DB administrator, System developer, or database, users., , , , Database application: Database application may be Departmental, Personal, organization's, and / or Internal., , , , DBMS: Software that allows users to create and manipulate database access,, , , , Database: Collection of logical data as a single unit., , Database Environment:, One of the primary aims of a database is to supply users with an abstract view of data, hiding a, certain element of how data is stored and manipulated. Therefore, the starting point for the, design of a database should be an abstract and general description of the information needs of the, organization that is to be represented in the database. And hence you will require an environment, to store data and make it work as a database. In this chapter, you will learn about the database, environment and its architecture.

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A database environment is a collective system of components that comprise and regulates the, group of data, management, and use of data, which consist of software, hardware, people,, techniques of handling database, and the data also., Here, the hardware in a database environment means the computers and computer peripherals, that are being used to manage a database, and the software means the whole thing right from the, operating system (OS) to the application programs that include database management software, like M.S. Access or SQL Server. Again the people in a database environment include those, people who administrate and use the system. The techniques are the rules, concepts, and, instructions given to both the people and the software along with the data with the group of facts, and information positioned within the database environment.

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Database Architecture:, , An early proposal for a standard terminology and general architecture for database systems was, produced in 1971 by the DBTG (Data Base Task Group) appointed by the Conference on Data, Systems and Languages (CODASYL, 1971). The DBTG recognized the need for a two-level, approach with a system view called the schema and user views called sub-schemas., , The levels form a three-level architecture that includes an external, a conceptual, and an internal, level. The way users recognize the data is called the external level. The way the DBMS and the, operating system distinguish the data is the internal level, where the data is stored using the data, structures and file. The conceptual level offers both the mapping and the desired independence, between the external and internal levels.