Eliminate repeating groups, Database Management System

Assignment Help:

Eliminate Repeating Groups

The problem is, "Find out the list of employees, who knows DB2".

For this problem we require to perform an awkward scan of the list looking for references to DB2. This is ineffective and a very untidy way to retrieve information.

We change the relation to 1NF. Please note that in the Department-loc fields and conversion Department will be part of Employee relation. The Emp-ID in the Database relation matches the primary key in the employee relation, giving a foreign key for relating the two relations with a join operation. Now we can response the question by looking in the database relation for "DB2" and getting the list of Employees. Please note that in this design we require not add D-ID (Database ID). Just the name of the database would have been sufficient as the names of databases are original.

Employee Relation

 

 

Database Relation

Emp-ID

Emp-Name

D-ID

Emp-ID

Database-name

1

Gurpreet Malhotra

1

2

Access

2

Faisal Khan

2

4

DB2

3

Manisha Kukreja

3

3

FoxPro

4

Sameer Singh

4

1

Oracle

 

4

4

Oracle


Related Discussions:- Eliminate repeating groups

What are the constituents of file, What are the Constituents of File? Also ...

What are the Constituents of File? Also elaborates all the possible file operations? A file is organised logically as sequence of record. These records are mapped onto disk blo

Consistency error-database errors, Consistency error : These errors happen ...

Consistency error : These errors happen due to the inconsistent state of database caused may be due to wrong implementation of commands or in case of a transaction abort.  To overc

Development of large scale distributed real systems, Question: (a) What...

Question: (a) What are the challenges in the development of Large Scale Distributed Real Systems? (b) What is backward engineering and forward engineering in a design packa

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

Enterprise applications integration, The figure below depicts the conceptu...

The figure below depicts the conceptual diagram of a banking system. (a) Describe one example relevant to the system in figure, for each of the 4 types of enterprise appl

Determine the types of methods for retrieving rows in python, Describe the ...

Describe the two types of methods for retrieving rows in Python? Fetchone()- Returns the next row as a sequence Fetch all()- Returns the entire result set like a strin

What is the use of unique function, What is the use of unique function? ...

What is the use of unique function? UNIQUE function: If UNIQUE is specified then only unique values are used to computed the mean.

What are the advantages of logical databases, What are the advantages of Lo...

What are the advantages of Logical Databases? It offers a simple-to-use selection screens.  You can change the pre-generated selection screen to your needs.  It offers check f

Referential integrity constraint - relational constraints, It defines that ...

It defines that the tuple in one relation that refers to another relation must refer to an existing tuple in that relation. This constraint is states on two relations (not essentia

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