Relationship for college database, Database Management System

Assignment Help:

Using the concepts defined previous, we have identified that strong entities in COLLEGE database are FACULTY, STUDENT, COURSE and DEPARTMENT. This database also has one weak entity known as GUARDIAN. We can states the following relationships:

1. Head-of is a 1:1 relationship among FACULTY and DEPARTMENT.

Participation of the entity FACULTY is partial since not all the faculty members participate in this relationship, as the participation from department side is total, as every department has one head.

2. Works_in, is a 1:N relationship among DEPARTMENT and FACULTY.

Participation from both sides is total.

3. Opts, is a 1:N relationship among COURSE and STUDENT. Participation from student side is total because we are assuming that every student enrolled opts for a course. However the participation from the course side is partial, as there can be courses that no student has opted for.

4. Taught_by, is a M: N relationship between FACULTY and COURSE, as a faculty can teach a lot of courses and a course can be taught by a lot of faculty members.

5. Enrolled, is a 1: N relationship among STUDENT and DEPARTMENT as a student is allowed to enroll for only single department at a time.

6. Has, is a 1:N relationship among STUDENT and GUARDIAN as a student can have more than one local guardian and one local guardian is supposed to be related to one student only. The weak entity Guardian has total participation in the relation "Has".


Related Discussions:- Relationship for college database

What is relationship instance, What is relationship instance ? Relation...

What is relationship instance ? Relationship Instance - A relationship is a relation between two or more entities. An instance of relationship set is a set of relationships.

What is a foreign key, What is a foreign key, and what is it used for? ...

What is a foreign key, and what is it used for? A foreign key is used to establish relationships between relations in the relational model. Technically, a foreign key is a colu

Security-data fragmentation, Security: Data not needed by local applicatio...

Security: Data not needed by local applications is not stored at the site, therefore no unnecessary security violations may exist. But how can we carry out fragmentation? Fragm

Write the queries in relational algebra, Problem: You are given the fol...

Problem: You are given the following schema 1. Flights(flno, from, to, distance) 2. Aircraft(aid, flno, aname, cruisingRange) 3. Certified(eid, aid) 4. Employees(eid, ena

Data models, why older data models are being replaced by new data models....

why older data models are being replaced by new data models.

Deadlock prevention, Deadlock Prevention One of the easiest approaches ...

Deadlock Prevention One of the easiest approaches for avoiding a deadlock would be to obtain all the locks at the begin of the transaction. Though, this approach restricts conc

What is data definition language, What is data definition language? Explain...

What is data definition language? Explain it in detail? The SQL DDL allows specification of not only a set of relations, but also information after each relation, containing

Descrine an data dictionary, Describe an data dictionary? A data dictio...

Describe an data dictionary? A data dictionary is a data structure which keeps meta data about the structure of the database ie. the schema of the database.

Create a classification model, Use again the GE Flight Quest Data and build...

Use again the GE Flight Quest Data and build on the work done for homework 1 and 2. The goal is to create a classification model which classifies flights into "on-time" (you can de

Illustrate the term- abstracting out common behaviour, Illustrate the term-...

Illustrate the term- Abstracting Out Common Behaviour Inheritance is not every time recognised during analysis phase of development, thus it is necessary to re-evaluate object

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