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

Give the reasons for allowing concurrency, Give the reasons for allowing co...

Give the reasons for allowing concurrency? The reasons for allowing concurrency is if the transactions run serially, a short transaction might have to wait for a preceding long

Define the normalisation form, Define in which normalisation form if an att...

Define in which normalisation form if an attribute of a composite key is dependent on an attribute of other composite key. Ans: 3NF A relation is in 3 NF if an attribute of

Er model, explain the steps for reduction of er model into relational model...

explain the steps for reduction of er model into relational model?

What are the comparison operator in sql, What are the comparison operator i...

What are the comparison operator in SQL?  Comparison operator in SQL are =, LIKE and BETWEEN

Need for multiple access paths, Need for Multiple Access Paths In pract...

Need for Multiple Access Paths In practice, most of the online information systems need the support of multi-key files. For example, consider a banking database application hav

State about the use case diagram, State about the Use Case Diagram A u...

State about the Use Case Diagram A use case diagram represents a set of use cases, actors and their relationships. These diagrams shall be used to model context or requirement

Structure of the ldb, Though all the ABAP/4 Dictionary Structures that exis...

Though all the ABAP/4 Dictionary Structures that exists in the structure of the LDB, being described in Database Program, we are explaining the Dictionary Structures in the Report.

Define single valued and multivalued attributes, Define single valued and m...

Define single valued and multivalued attributes. Single valued attributes: attributes with a single value for a particular entity are known as single valued attributes. Mult

In tuple relational calculus p1- p2 is equivalent to, In tuple relational ...

In tuple relational calculus P1 → P2 is equivalent to ? A In tuple relational calculus P1→  P2 is equivalent to ¬P1 V P2. (The logical implication expression A  B, meaning

Security and integrity, Security And Integrity After Reading the concep...

Security And Integrity After Reading the concepts of database recovery in the last section, let us now deal with a vital concept that helps in minimizing consistency errors in

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