1. Database Administration:
The management of the physical realization of a database application
which includes physical database design and implementation, setting security and
integrity controls, monitoring system performance and reorganizing the database if
necessary.
A DBMS is a complex software package. Installing, running and upgrading a DBMS are
not trivial1
tasks. Even with personal computer-based systems, these tasks can require the
services of a database administrator (DBA). The DBA position is generally staffed by a
specialist who is trained in the administration of a particular DBMS. In smaller
companies instead of hiring a specialist, one of the lead developers may be asked to
perform DBA duties.
DBA Tasks:
• Enforces standards, policies and procedures:
Every database application requires protection established through consistent
enforcement of data policies, procedures and standards.
Data Policies are statements that make explicit the goals of data administration. For
example “Every user must have a password.”
Data Procedures are written outlines of actions to be taken in order to perform a
certain activity. For example, Backup and Recovery procedures should be
communicated to all involved employees.
Data Standards are explicit conventions and behaviors that are to be followed and
that can be used to help evaluate database quality. For example naming conventions
for database objects should be standardized for programmers.
• Planning:
A key administration function is involvement with the development of the
organization’s information architecture. Effective administration requires both the
understanding of the needs of the organization for information and ability to
contribute to the development of an information architecture that will meet the
diverse needs of the typical organization.
• Data Conflict Resolution:
Databases are intended to be shared and usually involve
data from several different departments of the organization. Ownership of data is a
ticklish issue at least occasionally in every organization. Database administrators are
well placed to resolve data ownership issues because they are not typically associated
with a certain department. Establishing procedures for resolving such conflicts is
essential. If the database administration is given a sufficient authority to mediate and
enforce the resolution of the conflict, they may be very effective in this capacity.
• Monitor and tune the database performance:
Because databases are dynamic, it is
impossible that the initial design of the database will be sufficient to achieve the best
processing performance for the life of the database. The performance of the database
(query and update processing time) needs to be constantly monitored. The design of
1
Not Important
2. the database must be frequently changed to meet new requirements and to overcome
degrading effects. Periodically, the database must be rebuilt, reorganized and
reindexed.
• Improving database query performance:
The workload against a database most
certainly will expand over time. Thus, some queries, which originally ran quickly
against a small database, may need to be rewritten in a more efficient form to run in a
satisfactory time against a fully populated database. Indexes may need to be added or
deleted to balance performance across all queries.
• Managing Data Security, Privacy and Integrity:
Protecting the Security, Privacy and
Integrity of the organizational databases rests with the database administration. DBA
is more required in the databases used in the Internet and Intranet in which the data is
distributed and is maintained on multiple sites.
• Data Backup and Recovery:
The DBA must ensure that backup procedures are
established that will allow the recovery of all necessary data. The loss may occur
through application failure, hardware failure, physical or electrical disaster or human
error.
In addition to these, the database administrator performs the following tasks also.
Undertaking physical database design.
Implementing a physical database design using a target DBMS.
Install and Upgrade DBMS.
Liaising2
with database application developers.
Developing test strategies.
Training users.
Ensuring documentation is complete including in-house produced material.
Keeping up to date with software and hardware developments and costs, and
installing updates as necessary.
2
Close bond, Interrelationship