Differentiate between various levels of data abstraction, Database Management System

Assignment Help:

Differentiate between various levels of data abstraction?

Data Abstraction - Abstraction is the procedure to hide the irrelevant things from the users and represent the relevant things to the user. Database systems are frequent used through non-computer professionals so in which the complexity must be hidden from database system users. This is done through defining levels of abstract as that the database may be viewed; there is logical view or external view, conceptual view and internal view or physical view.

1. External View - This is the highest level of abstraction as seen through a user. It describes only the part of whole database, that is relevant to a particular user.

2. Conceptual View - This is the next higher stages of abstraction that is the sum total of Database Management System user's views. It elaborates what data are in fact stored in the database. It contains information about whole database in terms of a small number of associatively easy structure.

3. Internal View - This is the lowest level of abstraction. It elaborates how the data are physically stored


Related Discussions:- Differentiate between various levels of data abstraction

Differentiate between a unique key and a primary key, Differentiate between...

Differentiate between a unique key and a primary key. - By default, clustered index on column are created by primary key while nonclustered index are created by unique key.

Objectives-the structured query language, Objectives After reading this...

Objectives After reading this part, you should be able to: Modify, create, and delete database schema objects; Update database using SQL command; Retrieve data f

Synonyms, Synonyms It allows short names or alternative names for objects....

Synonyms It allows short names or alternative names for objects. Example :               CREATE SYNONYM D30               FOR EMPD30;   Now if we give command:

Explain data dictonary on oracle, Explain data dictonary on oracle ? Da...

Explain data dictonary on oracle ? Data Dictionary - Data dictionaries are the system tables in which contain descriptions of the database objects and how they are structured.

Abap/4 program, It is not possible to make an ABAP/4 program, which having ...

It is not possible to make an ABAP/4 program, which having only Subroutines. False. We can make ABAP/4 program, which having only Subroutines.

How to deal with the authentication problem, Most computer systems authenti...

Most computer systems authenticate users by asking them for the user name and password. However, the user names and passwords often can be guessed by hackers. Suggest an automated,

Timestamp type, Do NOT use the timestamp type.  Use separate date and time ...

Do NOT use the timestamp type.  Use separate date and time data types only.  Figure out how to define an SQL insert statement that uses built-in SQL (or MySQL) functions to define

What is olap, What is OLAP? OnLine Analytical Processing (OLAP) is a Bu...

What is OLAP? OnLine Analytical Processing (OLAP) is a Business Intelligence (BI) reporting system. OLAP gives the user with the capability to sum, count, average and do other

What is property - properties of a database, What is property - properties ...

What is property - properties of a database ? It is an integrated collection of logically related records. It consolidates separate files into a common pool of data records and

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