Conversion of er diagram to relational database, Database Management System

Assignment Help:

Conversion of entity sets:

I)   For  every  strong  entity  type  E  in  the  ER  diagram,  we  make  a  relation  R containing all the easy attributes of E. The relation R primary key will be one of the key attributes of R.

For example, the STUDENT, FACULTY, COURSE and DEPARTMENT tables in Figure.

STUDENT

ROLLNO: Primary Key

NAME

ADDRESS

 

 

 

 

 

 


 

 

FACULTY

ID: Primary

Key

NAME

ADDRESS

BASIC_SAL

 

 

 

 

 

 

 

 

 

 

 

 

COURSE

COURSE_ID: Primary Key

COURSE_NAME

DURATION

 

 

 

 

 

 

 

DEPARTMENT

D_NO: Primary Key

 

 

 

 

 

For each weak entity type W in the E R Diagram, we make another relation R that have all easy attributes of W. If E is an owner entity of W then key attribute of E is also contained in R. This key attribute of R is set as a foreign key attribute of R. Now the mixture of primary key attribute of owner partial key and entity type of weak entity type will form the key of the weak entity type.

The weak entity GUARDIAN, where the key field of student entity

RollNo has been added.

RollNo            Name

(Primary Key)

Address

Relationship

 

 

 

 

 

 

 

 


Related Discussions:- Conversion of er diagram to relational database

Write short notes on extension and intension, Write short notes on extensio...

Write short notes on extension and intension? In any data model, it is significant to distinguish among the description of the database and the database itself the description

Explain the outer join, Define Outer join Outer join - If there are any...

Define Outer join Outer join - If there are any type of values in the one table that do not have corresponding value(s) in the other, in an equi-join which will not be selected

Data warehouse, #queDefine a job scheduling strategy that will meet busines...

#queDefine a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pic

Text mining, Text Processing: Use readLines to read SOU.txt into R. Cr...

Text Processing: Use readLines to read SOU.txt into R. Create a vector called Pres containing the names of the presidents giving each speech. To do this, rst identify the lin

The internal or physical level in dbms, The Internal or Physical Level ...

The Internal or Physical Level The collection of files permanently stored on secondary storage devices is called as the physical database. The internal or physical level is t

List the sql domain types, List the SQL domain Types? SQL supports the ...

List the SQL domain Types? SQL supports the following domain types. 1) Char(n) 2) varchar(n) 3) int 4) numeric(p,d) 5) float(n) 6) date.

Consistency, what do you mean by consistency in rdbms?

what do you mean by consistency in rdbms?

Entity-relationship diagram, 1. Item based services will be charged fixed p...

1. Item based services will be charged fixed prices, and time-based will be charged variably depending on time. Such as per hour. Item-based: Fixed, pedicure, waxing, threading, fa

Indexed (indexed sequential) file organisation, Indexed (Indexed Sequential...

Indexed (Indexed Sequential) File Organisation It organises the file like a big dictionary, i.e., records are kept in order of the key but an index is stored which also allows

List the types of authorization, List the types of authorization. A) R...

List the types of authorization. A) Read authorization B) Write authorization C) Update authorization D) Drop authorization

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