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 .

Comments

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Compare the difference between the following:

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