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

Relationship sets, A relationship set is a set of relationships of the simi...

A relationship set is a set of relationships of the similar type. For example, let consider the relationship among two entities sets course and student. Collection of all the in

Entity identifier key attributes, An entity type usually has an attribute w...

An entity type usually has an attribute whose values are distinct for every individual entity in the collection. Such an attribute is known as a key attribute and its values can be

What is recovery management component, What is recovery management componen...

What is recovery management component? Ensuring durability is the responsibility of a software component of the base system known as the recovery management component.

What are the types of reference, What are the types of reference?explain it...

What are the types of reference?explain it with suitable examples? Object oriented language given the ability to refer the object attribute of the type can be referred to the s

What is the aim of object design, What is the aim of object design The ...

What is the aim of object design The aim of object design is to identify object which the system   contains and the interactions among them. The system implements specification

Key, Q.   Explain the terms key constraints participation constraints and m...

Q.   Explain the terms key constraints participation constraints and mapping caradinalities in ER model.  Participation Constraints :   The participation of an entity set E i

Give detail description on transactions, Give detail description on Transac...

Give detail description on Transactions. - Using transactions we can group all SQL commands into a single unit. - Transaction begins with some task and finishes only when a

Why are cursors necessary in embedded sql, Why are cursors necessary in emb...

Why are cursors necessary in embedded SQL? A cursor is an object used to store the output of a query for row-by-row processing through the application programs. SQL statements

Using column aliases-data manipulation language, Using Column aliases E...

Using Column aliases Example: To print column names as NAME and ANNUAL SALARY SELECT ENAME "NAME", SAL*12 "ANNUAL SALARY" FROM EMP;

Relational schema for person, Example: RELATIONAL SCHEMA for PERSON: ...

Example: RELATIONAL SCHEMA for PERSON: PERSON (PERSON_ID: integer, NAME: string, AGE: integer, ADDRESS: String) RELATION INSTANCE In this instance, m = 3 and n = 4

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