Eliminate redundant data, Database Management System

Assignment Help:

 Eliminate Redundant Data

In the "Database Relation" above, the primary key is made up of the D-ID and the Emp-ID. The database-name relies only on the D-ID. The similar database-name will appear redundantly every time its associated D-ID appears in the Database Relation. The database relation has redundancy, for example D-ID value 4 is oracle is repetitive twice. In addition, it also experiences insertion anomaly that is we cannot enter Sybase in the relation as no employee has that skill.

The deletion anomaly also exists. For instance, if we remove employee with Emp-ID 3; no employee with FoxPro knowledge lefts and the information that D-ID 3 is the code of FoxPro will be gone.

To avoid these troubles, we require second normal form. To achieve this, we isolate the attributes depending on both parts of the key from those depending only on the D- ID. This result in two relations: "Database" which gives the name for every D-ID,

and "Emp-database" which lists the databases for each employee. The employee relation is already in 2NF as all the EMP-ID determines all different attributes

Employee Relation

 Emp-ID

Emp-Name

1

Gurpreet Malhotra

2

Faisal Khan

3

Manisha Kukreja

4

Sameer Singh

 

Emp-database

Relation

Emp-ID

D-ID

2

1

4

2

3

3

1

4

4

4

 

 

 

 

Database Relation

D-ID

Database

1

Access

2

DB2

3

FoxPro

4

Oracle


Related Discussions:- Eliminate redundant data

What are the acid properties?, Question 1 What are the advantages of DBMS ...

Question 1 What are the advantages of DBMS approach in managing data? Question 2 What are the services provided by a database system Question 3 List and briefly describe

The transactions, The Transactions- A transaction is definite as the unit o...

The Transactions- A transaction is definite as the unit of work in a database system. Database systems that deal with a huge number of transactions are also termed as transaction p

I want a professional with strong it background, I want a professional with...

I want a professional with strong IT background who provide me timely assignments Project Description: I want a professional who can do my assignments for my major i.e. Infor

What are the advantages of dbms, What are the advantages of DBMS ? 1. ...

What are the advantages of DBMS ? 1. Centralized Management and Control - One of the major advantages of using a database system is in which the organization could exert, thr

Illustrate the class diagram for class room scheduling, Illustrate the clas...

Illustrate the class diagram for class room scheduling system If in any college, the number of classrooms are limited which have to be allocated to various classes and instruct

ER diagram, #question. acompani datdbase needs to store information about e...

#question. acompani datdbase needs to store information about employees (identified by a social security number,with salary and phone as attributes) and departments (identified by

Explain th process to avoid re-computation, Saving Derived Attributes to Av...

Saving Derived Attributes to Avoid Re-computation Data that is derived from other data should be stored in the computed form to avoid re-computation. For this, we could define

Physical location of record is determined by which formula, The physical lo...

The physical location of a record is determined by which mathematical formula that transforms a file key into a record location? The physical location of a record is determined

What are the benefits of document scanning, What are the benefits of docume...

What are the benefits of document scanning? Document scanning, in addition to being cost-efficient, also enhances productivity. This service enhances security as you set the pa

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