Functions of DBMS

Different function that the DBMS performed: 

• Data Processing
•  A user accessible Catalog
•  Transaction Support
•  Concurrency Control Services
•  Recovery Services
•  Authorization Services
•  Support for Data Communication
•  Integrity Services

DBMS lies at the heart of the course; it is the most important component of a database system. To understand the functionality of DBMS it is necessary that we understand the relation of database and the DBMS.

Two important functions that the DBMS performs are:

1. User management
2. Data Management

The detailed description of the above two major activities of DBMS is given below;

·       Data Processing:-

           By Data management we mean a number of things it may include certain operations on the data such as: creation of data, Storing of the data in the database, arrangement of the data in the databases and data-stores, providing access to the data in the database, and placing of the data in the appropriate storage devices. These action performed on the data can be classified as data processing.

·       A User Accessible Catalog:-

          DBMS has another very important task known as access proviso to catalog. Catalog is an object or a place in the DBMS which stores almost all of the information of the database, including schema information, user information right of the users, and many more things about the database. Modern relational DBMS require that the Administrative users of the database should have access to the catalog of the database.

·       Transaction Support:-

           DBMS is responsible for providing transaction support. Transaction is an action that is used to perform some manipulation on the data stored in the database. DBMS is responsible for supporting all the required operations on the database, and also manages the transaction execution so that only the authorized and allowed actions are performed.

Concurrency Support:-

         Concurrency support means to support a number of transactions to be executed simultaneously, Concurrency of transactions is managed in such a way that if two or more transactions is making certain processing on the same set of data, in that case the result of all the transactions should be correct and no information should be lost.

·       Recovery Services:-

          Recovery services mean that in case a database gets an inconsistent state to get corrupted due to any invalid action of someone, the DBMS should be able to recover itself to a consistent state, ensuring that the data loss during the recovery process of the database remains minimum.

·       Authorization Services:-

              The database is intended to be used by a number of users, who will perform a number of actions on the database and data stored in the database, The DBMS is used to allow or restrict different database users to interact with the database. It is the responsibility of the database to check whether a user intending to get access to database is authorized to do so or not. If the user is an authorized one than what actions can he/she perform on the data?

Support for Data Communication:-

             The DBMS should also have the support for communication of the data indifferent ways. For example if the system is working for such an organization which is spread across the country and it is deployed over a number of offices throughout the country, then the DBMS should be able to communicate to the central database station. Or if the data regarding a product is to be sent to the customers worldwide it should have the facility of sending the data of the product in the form of a report or offer to its valued customers.

·       Integrity Services:-

         Integrity means to maintain something in its truth or originality. The same concept applies to the integrity in the DBMS environment. Means the DBMS should allow the operation on the database which are real for the specific organization and it should not allow the false information or incorrect facts.