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

Draw an er diagram with primary key for a farm, Draw an ER diagram that rep...

Draw an ER diagram that represents the information described below. Show all entity sets, relationship sets, primary keys, and the mapping cardinality of the relationship sets.

System error-database errors, System error :These contain errors in databas...

System error :These contain errors in database system or the OS, example, deadlocks.Such errors are fairly hard to detect and need reprogramming the erroneous components of the sys

Discuss the method for a hash file to expand shrink dynamic, Discuss the me...

Discuss the methods for a hash file to expand and shrink dynamically. What are the advantages and disadvantages of each? The hashing methods that permit dyanamic file expansi

Dealing with constraints violation, If the deletion violates referential in...

If the deletion violates referential integrity constraint, then three alternatives are available: Default option: - refuse the deletion. It is the job of the DBMS to describ

Data dictionary, The database is to record information about artists for a ...

The database is to record information about artists for a (music) production company. An artist is the name of a singer or band; the name of the artist, the year the artist started

Explain data independence, Explain data independence ? Data independenc...

Explain data independence ? Data independence is the capacity to modify the schema at one stage of a database system without having to change the schema at the further level.

Define the unique constraints for the table client, Define the following co...

Define the following constraints for the table client. (i) BAL_DUE must be at least 1000. (ii) NAME is a unique key. (i)ALTER TABLE CLIENT ADD CONSTRAINT CLIENT_BAL_DUE_C1

Heuristics, Benefits of using heuristics

Benefits of using heuristics

Differentiate between a global and a local temporary table, Differentiate b...

Differentiate between a Global and a Local temporary table? - A local temporary table exists only for the duration of a connection or if defined inside a compound statement, fo

Improved availability, Improved availability: The data in a distributed sys...

Improved availability: The data in a distributed system may be replicated so that it is at more than one site. Thus, the failure of a node or a communication link does not necessar

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