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Explain the four actors on the scene of Database?

  • For a small personal database, one person defines, constructs and manipulates the database .
  • For a large organization, many people are involved in the design, use and maintenance of the large database
  • Two types of actors of DBMS:
    1. Actors on the Scene (day-to-day use of large database )
    2. Workers behind the Scene ( work to maintain database environment and are not involved in its contents )

Actors on the Scene
Database administrators (DBA) are responsible for:

Authorizing access to the database

Coordinating and monitoring its use

Acquiring software and hardware resources


Database designers are responsible for:

Identifying the data to be stored

Choosing appropriate structures to represent
and store this data .


End users - People whose jobs require access to the database.

Types of End Users

• Casual end users

• Naive or parametric end users

• Sophisticated end users

• Standalone users


System analysts

Determine requirements of end users

Application programmers

Implement these specifications as programs




Workers behind the Scene


DBMS system designers and implementers

Design and implement the DBMS modules and interfaces as a software package

Tool developers

Design and implement tools

Operators and maintenance personnel

Responsible for running and maintenance of hardware and software 
environment for database system .
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