DBMS FUNCTIONS in DBMS

DBMS FUNCTIONS: 

       DBMS performs several important functions that guarantee the integrity and consistency of the data in the database. Those functions transparent to end users and can be accessed only through the use of DBMS. They include:

• Data Dictionary Management 
• Data Storage Management 
• Data transformation and Presentation
•  Security Management
•  Multiple Access Control
•  Backup and Recovery Management
•  Data Integrity Management
•  Database Access Languages 
• Databases Communication Interfaces

 Data Dictionary Management:

•        DBMS stores definitions of database elements and their relationship (Metadata) in the data dictionary. 
• The DBMS uses the data dictionary to look up the required data component structures and relationships
•  Any change made in database structure is automatically recorded in the data dictionary. 

Data Storage Management:

•   Modern DBMS provides storage not only for data but also for related data entities
•  Data Storage Management is also important for database “performance tuning”. 
• Performance tuning related to activities that make database more efficiently

 Data Transformation and Presentation:

•       DBMS transforms entered data to confirm to required data structures. 
•      DBMS formats the physically retrieved data to make it confirms to user’s logical expectations.  
•          DBMS also presents the data in the user’s expected format.

Security Management: 

•    DBMS creates a security system that enforces the user security and data privacy
•   Security rules determines which users can access the database, which data items each user can access etc.
•  DBA and authenticated user logged to DBMS through username and password or through Bio metric authentication such as Finger print and face reorganization etc.

 Multiuser Access Control:

•  To provide data integrity and data consistency, 
• DBMS uses sophisticated algorithms to ensure that multiple users can access the database concurrently without compromising the integrity of database

 Backup and Recovery Management:

•  DBMS provides backup and recovery to ensure data safety and integrity.
•  Recovery management deals with the recovery of database after failure such as bad sector in the disk or power failure.
•  Such capability is critical to preserve database integrity.

 Data Integrity Management:

•  DBMS provides and enforces integrity rules, thus minimizing data redundancy and maximizing data consistency.
•  Ensuring data integrity is especially important in transaction- oriented database systems.

 Database Access Languages:

•  DBMS provides data access through a query language.
•  A query language is a non-procedural language i.e. it lets the user specify what must be done without specifying how it is to be done.
•  SQL is the default query language for data access.

 Databases Communication Interfaces:

•  Current DBMS’s are accepting end-user requests via different network environments. 
• For example, DBMS might provide access to database via Internet through the use of web browsers such as Mozilla Firefox or Microsoft Internet Explorer