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

Rules of data normalisation, Rules Of Data Normalisation  Let us now su...

Rules Of Data Normalisation  Let us now summarise Normalisation with the help of various clean rules. The following are the necessary rules for the Normalisation process: 1.

Which is the properties of entities, Which is the properties of entities? ...

Which is the properties of entities? Attributes is the properties of entities.

What is dag, What is DAG? The class-subclass relationship is shown by a...

What is DAG? The class-subclass relationship is shown by a directed acyclic graph.eg: employees can be temporary or permanent. We might be create subclasses temporary \and perm

Er schema can be represented by relation schemas , Q. Describe how an ER sc...

Q. Describe how an ER schema can be represented by relation schemas and constraints arising from ER design can be mapped to constraints on a relation schema.     The entity rela

Basic set operation, These are the binary operations; i.e., each is applied...

These are the binary operations; i.e., each is applied to two relations or sets. These two relations can be union compatible excluding in case of Cartesian product. Two relations R

Serialisable schedules, Serialisable Schedules: If the processes of two tra...

Serialisable Schedules: If the processes of two transactions conflict with each other, how to verify that no concurrency related problems have happened? For this, serialisability t

View serialiabilty-labelled precedence graph, how to construct labelled pre...

how to construct labelled precedence graph for view serialiability.please explain insteps with one solved examples

How to apply the bcnf decomposition , Consider the following relational sch...

Consider the following relational scheme: R (a,b,c,d,e,f) and its corresponding set of FDs {d→ a, be → c, ac → e, b → f, f → d, a → c}. a. Is the following decomposition i) non

Is siteground database over limit, I am using Siteground. And my databas...

I am using Siteground. And my database is full of limit so need someone who reduces the data which no need. This is very simple and simple task. Skills required are Databa

Enforce referential integrity, Use Access 2007 to create a database calle...

Use Access 2007 to create a database called UniLib.mdb. - this file should be created on your personal drive at the university (or C: if you're using Access 2007 at home) and t

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