3. Database Administrator

 The term Database Administrator simply refers to a person having central control over data and programs accessing that data.

Duties of the Database Administrator

The duties of the database administrator include: 

Scheme definition: the creation of the original database scheme. This involves writing a set of definitions in a DDL (data storage and definition language), compiled by the DDL compiler into a set of tables stored in the data dictionary.

Storage structure and access method definition: writing a set of definitions translated by the data storage and definition language compiler

Scheme and physical organisation modification: writing a set of definitions used by the DDL compiler to generate modifications to appropriate internal system tables (e.g. data dictionary). This is done rarely, but sometimes the database scheme or physical organisation must be modified.

Granting of authorisation for data access: granting different types of authorisation for data access to various user

Integrity constraint specification: generating integrity constraints. These are consulted by the database manager module whenever updates occur.