Define physical and logical data independence, Database Management System

Assignment Help:

Define physical and logical data independence. How does this architecture help in achieving these?

Data independence entails that change in one view must not need a change in the view(s) above. There are two sorts of data independence: logical and physical. The meaning of Logical data independence is that the conceptual view can be changed without influencing the existing external view, that is a given record may be spilt or combined along with other records but the external views need not be modified to reflect this. The meaning of Physical data independence is that the physical storage structures or devices employed to store the data can be changed without effecting the existing conceptual view or external view, that is if earlier indexed sequential files are employed to store data and then the B- trees are used, even then the upper layers must not be effected.


Related Discussions:- Define physical and logical data independence

What is object identity, What is object identity? An object retains its...

What is object identity? An object retains its identity even if some or all the values of variables or explanations of methods change overtime.

Write the sql queries using data manipulation language, Problem 1. Writ...

Problem 1. Write the SQL queries using Data Manipulation Language (DML) statements. Insert values into student table with field names using insert command Display the

Which is a valid sql type, Which is a valid SQL type? A valid SQL Shoul...

Which is a valid SQL type? A valid SQL Should be in CHARACTER it is should be NUMERIC and FLOAT.

What is known as a search key, What is known as a search key? An attrib...

What is known as a search key? An attribute or set of attributes used to look up records in a file is known as a search key.

Difference among a primary index and a secondary index, What is the differe...

What is the difference among a primary index and a secondary index? Primary Index: A primary index is an ordered file whose records are of fixed length along with two fields.

Describe the responsibilities of the dba and the database, Describe the res...

Describe the responsibilities of the DBA and the database designer ? The responsibilities of DBA and database designer are: 1. Planning for the database's future storage needs

ENTITY DIAGRAMS IN FIRST NORMAL FORM, CAN SOMEONE HELP ME WITH ENTITY DIAGR...

CAN SOMEONE HELP ME WITH ENTITY DIAGRAMS IN FIRST NORMAL FORM?

Define the terms key attribute and value set, Define the terms i) Key attr...

Define the terms i) Key attribute ii) Value set Key attribute: An entity type usually has an attribute whose values are exact from each individual entity in the collection. Su

Define the canonical cover, Define the Canonical cover Ans: A canonical...

Define the Canonical cover Ans: A canonical cover F c for F is a set of dependencies like F logically implies all dependencies in F c , and F c logically entails all dependen

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