Functions of database

 

Function of database

The following are  the important function of DBMS 

1. Data dictionary management

        Database contains two tupes of data. They are enduser data  and meta data . DBMS stores these data in a dictionary called data dictionary. when end user needs a particular data, the DBMS uses the data dictionary and provides the data to the user. this function makes the database access easy. also any change to the database structures are automatically recorded in the data dictionary. called function of database.

        2. Data storage management

        DBMS  creates complex structures required for data storage. The users are relieved from defining, programming and implementing the complex physical data characteristics. called function of database.

        3.Data transformation and persentation 

        DBMS transforms the entered data into required data structures. Also it retrieves the data needed by the user and presents it the user in an order.called function of database.

        4.Security management

        

        DBMS guards the database by granting privileges to individual users and group users. Depending on the privilege they are allowed to access data. Unauthorised users are not allowed to access the database.

         5.Mutiuser access control

        When more then one user access the database, there is a possiblity for the following to happen.

• More then one user tries to update the same data.
• one user is reding and other is updating the same data. - Because of the above reasons the data in the database becomes inconsistent and loses integrity. to avoid this, DBMS  uses tools to provide data consistency and integrity during multiple access. called function of database. 

        6.Backup and recovery management 

        Backup is a process of copying the whole database onto a cheap storage medium for data safety. DBMS provides special tools that allow the DBA to perform regular backup procedures. Recovery is a process of  restoring a database to the correct state in case of any failure. This can be achieved by coping the files form the physical backup.

        7.Data integrity management 

        Data integrity refers to the process of maintainig the correctness and consistency of data. DBMS enforces this by a series of integrity constraints or rules.

       8.Communication interfaces

        DBMS means database management system  provides acess to the database through internet. that is called function of database.

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