Describe physical data independence, Database Management System

Assignment Help:

Describe Physical Data independence ?

Physical Data Independence - It is capacity to modify the internal schema without having to change conceptual schema. Therefore, the external schemas required not be changed as well. Changes to the internal schema might be required because some physical files had to be reorganized to improve the performance of retrieval or update. If the similar data as before remains in the database, the conceptual schema requires not be changed.

Related Discussions:- Describe physical data independence

Explain the project-join normal form, Explain the Project-Join normal form ...

Explain the Project-Join normal form A relation R is in PJNF along with respect to a set of functional dependencies D if for all join dependencies of the outline *(R 1 , R 2 ,

Search the salary of employees who are not ‘analyst’ , Example- Search the ...

Example- Search the salary of employees who are not 'ANALYST' but get a salary below than or equal to any people employed as 'ANALYST'. SELECT EMPNO, ENAME, JOB, SAL FROMEMP

Computer, what is object-identity

what is object-identity

Join relation of two tuples, Consider the join of a relation R with relatio...

Consider the join of a relation R with relation S. If R has m tuples and S has n tuples, then the maximum size of join is: If R has m tuples and S has n tuples then maximum siz

Explain the check clause, Explain the Check Clause The CHECK clause is ...

Explain the Check Clause The CHECK clause is employed to at the end of a CREATE TABLE statement specify table constraints. This is known as table-based constraint because it ap

Data warehousing, job scheduling for different cubes

job scheduling for different cubes

Short note on mid square method of hashing, Short Note on mid Square Method...

Short Note on mid Square Method of hashing? Mid square method of hashing: In the method midsquare hashing, the key is squared and the address selected from the center of the s

Although how will the system recover, Although how will the system recover ...

Although how will the system recover The selection of REDO or UNDO for a transaction for the recovery is completed on the basis of the state of the transactions. This state is

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

Example of ancestry database , Ancestry database records information about ...

Ancestry database records information about family trees . Following information is recorded about each person: FIRSTNAME first name SURNAME surname MNAME maiden name (if

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages