Introduction of DBMS Data Base Management System

     

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       Introduction of DBMS

     A database management system (DBMS) is system software used to manage the organization, storage, access, security and integrity of data in a structured database.
The nature of database management systems has dramatically since the 1960 as the demand for data storage has increased and the technology to store data has plummeted.

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Types of Data Base
     A database can be a set of flat files stored on computer tape or disk or it could consist of database tables that are managed by a Database Management System (DBMS).
There are different types of DBMS products: relational, network and hierarchical. The most widely commonly used type of DBMS today is the Relational Database Management Systems (RDBMS).

Types of DBMS Components        

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    Some Data Base Management Systems can be accessed directly using programming languages such as COBOL while others provide their own programming language for interacting with the database.Many DBMS applications also provide reporting and query tools to view data in the database.
• Data Definition.  One very important role of a database management system (DBMS) is to maintain the data definitions for each table and columns in the database.

Each piece of data must be assigned a name, a data type (e.g. date, alphanumeric, numeric) and a mandatory/optional status.  Most DBMS packages will enforce these rules when rows are added to
the database.

               

Data Security in DBMS Architecture...
Another important role of a Database Management System (DBMS) is to enforce data security.
Based on the assigned roles of users, a DBMS system can ensure that a given user only has read and/or update access to appropriate columns in the database.  This ensures that private data such as salary information is only accessible to the appropriate parties

      

     
         DBMS Audit Trails        

                Most DBMS applications can track changes made to tables in the database.  Along with the prior version of the data, the DBMS will record the identify of the person who altered the data.
Maintaining audit trails on important data is another important role for database management systems.

               

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