Role of Database Administrator.

Typically there are three types of users for a DBMS:
1. The END User who uses the application. Ultimately he is the one who actually puts the data into the system into use in business. This user need not know anything about the organization of data in the physical level.
2. The Application Programmer who develops the application programs. He/She has more knowledge about the data and its structure. He/she can manipulate the data using his/her programs. He/she also need not have access and knowledge of the complete data in the system.
3. The Data base Administrator (DBA) who is like the super-user of the system. The role of DBA is very important and is defined by the following functions.
• Defining the schema: The DBA defines the schema which contains the structure of the data in the application. The DBA determines what data needs to be present in the system and how this data has to be presented and organized.
• Liaising with users: The DBA needs to interact continuously with the users to understand the data in the system and its use.
• Defining Security & Integrity checks: The DBA finds about the access restrictions to be defined and defines security checks accordingly. Data Integrity checks are defined by the DBA.
• Defining Backup/Recovery Procedures: The DBA also defines procedures for backup and recovery. Defining backup procedure includes specifying what data is to be backed up, the periodicity of taking backups and also the medium and storage place to backup data.

• Monitoring performance: The DBA has to continuously monitor the performance of the queries and take the measures to optimize all the queries in the application.