A person who has central control over the whole
database system is a database administrator (DBA). His functions may be
summarized as below
·
Schema definition: The DBA creates the original database schema or the overall design of
the database.
·
Storage structure and access-method definition: The DBA is aware of certain details of physical
organization of the data i.e. how records occupy storage locations or bytes and
the methods to access those data.
·
Schema and physical-organization modification: The DBA can change the schema and physical
organization according to the demands of the organization, or simply to improve
performance. This can be done without affecting application programs at logical
level.
·
Granting of authorization for data access: The DBA can grant different types of authorization to
different users and hence control which user has the right to access which
parts of the database. This enhances to keep the system secure.
·
Routine maintenance: Some examples of DBA’s routine maintenance activities are as follows:
i)
Backup the
database periodically to tapes or remote servers so that they can be recovered
in case of disasters such as database sabotage.
ii)
Ensure enough
disk space is available for normal operations and upgrade disk space as
required.
iii)
Monitor jobs
running in the database and ensure overall performance is good.
Copyright @ by Rosina S Khan
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