Database administrator, Database Management System

Assignment Help:

Database Administrator

One of the main perpose for having the database management system is to have control of both data or programs accessing that data. The person having like control over the system is called as the database administrator (DBA). The DBA administers the 3 stages of the database and tells the global view or conceptual level of the database. The DBA also displays the external view of the applications and several users and is responsible for the definition and execution of the internal level, as well as the storage structure and access techniques to be used for the optimum performance of the DBMS. A modification to any of the 3 levels due to varies in the organisation and/or emerging technology is under the control of the DBA.

Mappings among the internal and the conceptual levels, as well as between the conceptual and external levels, are also describe through the DBA. The DBA is responsible for granting permission to the users of the database and remainsthe profile of each user in the database. This profile defines the permissible activities of a user on that portion of the database accessible to the user through one or more user views. The user profile could be used by the database system to confirm in which a particular user can present a given operation on the database.

The DBA is also responsible for describing procedures to recover the database from natural, failures due to human, or hardware causes along  with minimal loss of data. This recovery procedure should permit the organisation to continue to function and the intact portion of the database has to continue to be available.

Therefore, the functions of DBA are:

  • Schema definition: Formation of the original database schema is accomplished through writing a set of definitions which are translated through the DDL compiler to a set of tables that are always stored in the data dictionary.
  • Storage Structure and access method definition: The Formation of appropriate storage structure and access techniques is accomplished through writing a set of definitions which are translated by the definition language compiler and data storage.
  • Schema and Physical organisation modification: DBA includes either the changes of the database schema or the description of the physical storage organisation. These changes, though relatively rare, are accomplished by writing a set of definitions which are used through  either the data storage or the DDL compiler and definition language compiler to make modification to the appropriate internal system tables (for example the data dictionary).
  • Granting of authorisation for data access: DBA allows the granting of different types of authorisation for data access to the various users of the database.
  • Integrity constraint specification: The DBA shows the constraints. These constraints are put in a special system structure, the data dictionary which is consulted through the database manager prior to any data manipulation. Data Dictionary is one of the precious tools in which the DBA uses to carry out data administration.

Related Discussions:- Database administrator

Explain the functional mode with help of an example, Explain the Functional...

Explain the Functional Mode with help of an example. Functional Model  The functional model shows a computation and functional derivation of data values in it without ind

What are the dbms languages, What are the DBMS languages? Briefly explain?...

What are the DBMS languages? Briefly explain? Data Definition language (DDL):A database schema is specified through a set of definitions expressed through a special language

Explain data models namely relational network - hierarchical, Explain the t...

Explain the three data models namely relational, network and hierarchical and evaluate their relative advantages and disadvantages. Hierarchical Model: In hierarchical model, da

Define hash files organization, Define Hash files organization a. Hashi...

Define Hash files organization a. Hashing includes computing the address of a data item by calculating a function on the search key value.   b. A hash function h is a functi

Difference among a database schema and a database state, What is the differ...

What is the difference among a database schema and a database state? The collection of information stored in database at particular moment in time is known as database state a

design the logic using looping structure, 1. Design the logic, using a loo...

1. Design the logic, using a looping structure, for a program that outputs every even number from 1 through 25 along with its square and cube. 2. Mr. Sanchez owns 12 apartme

Describe specialsation and generalization, Describe Specialsation and gener...

Describe Specialsation and generalization? Specialisation /generalization: This is a top down and bottom up approach to the design of database. It displays the IS_A relation

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd