Fds in relationships and teaches relationship, Database Management System

Assignment Help:

FDs in Relationships:

 Enrols Relationship: None as it is many to many

Teaches Relationship: Course code → Instructor

Instructor → Course code

The next question is:  How do we recognize the functional dependence in a database model?

Functional dependencies occur from the nature of the actual world that the database models. Often A and B are facts about an entity where A may be some identifier for the entity and B some characteristic. Functional dependencies cannot be automatically determined by studying one or more cases of a database. They can be determined only by a careful study of the actual world and a clear understanding of what every attribute means.

 There are no thumb rules for determining FDs.

Functional dependence is an vital concept and a large body of formal theory has been developed about it.

 


Related Discussions:- Fds in relationships and teaches relationship

Trigger , Flights(FlightNo, DeptDateTime, Origin, ArrivalDateTime, Destinat...

Flights(FlightNo, DeptDateTime, Origin, ArrivalDateTime, Destination, Capacity, SoldSeats) Tickets(FlightNo, Seat, CustID) Where - flightNo is the PK of the flights table - DeptDa

Optimistic concurrency control, Optimistic Concurrency Control Is locki...

Optimistic Concurrency Control Is locking the only way to stop concurrency related problems? There exist some other ways too. One such way is known as an Optimistic Concurrency

What is candidate key, What is Candidate Key Super Key or Candidate Ke...

What is Candidate Key Super Key or Candidate Key: It is such an attribute of a table that can uniquely recognize a row in a table. Generally they have unique values and can n

BI, (a) Why did SAP introduce the extended star schema?

(a) Why did SAP introduce the extended star schema?

What is storage manager, What is storage manager?  A  storage  manager ...

What is storage manager?  A  storage  manager  is  a  program  module  that  gives  the  interface  between the Low level data  kept in a database and the application programs

Object query language and odmg schema , (a)    Provide the description of t...

(a)    Provide the description of the following ODMG schema in the Object Definition Language (ODL). (b)   Based on the above object database, write the following queries i

Draw enhanced er-diagram for hierarchy of a student database, Draw an EER d...

Draw an EER diagram that captures the "is-a" hierarchy of students in another simple database. The database captures both the "basic" information (say, student ID and student name)

Decompose the table - 3nf or bcnf, Decompose the table with the following ...

Decompose the table with the following description and functional dependencies into a set of equivalent tables normalized to 3NF or BCNF. A long-standing international treaty am

Need website hacking security test, We want have a website; we need to test...

We want have a website; we need to test the security of our website. You need to: -Try to bypass our security by simulate a website hacking -Try some hack Techniques like

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