Prove that a relation which is 4nf must be bcnf, Database Management System

Assignment Help:

Prove that a relation which is 4NF must be BCNF.  

Ans Let R be in 4NF.  Suppose it is not in BCNF.  Hence, there exists an FD X→Y in R such that x is not a super key. Although by the rule M1 X→Y|=x→→Y. Once again x here is not a super key.  This contradicts the fact that R is in 4NF.  Hence, our assumption is false.  Each R in 4NF should be in BCNF.


Related Discussions:- Prove that a relation which is 4nf must be bcnf

Database design in third normal form, The following data are required to be...

The following data are required to be stored by a family physician. Family#, FamilyAddress, Patient#, PatientName, ServiceCode, ServiceFee, ServiceDate A family can have seve

What is the meaning of redundant associations, Adding Redundant Association...

Adding Redundant Associations for Efficient Access The expression redundant association means using "duplicate association for proficient access". While analysis, it is not a

What are the different kinds of database end users, What are the different ...

What are the different kinds of database end users? Discuss the major activities of each? End-Users - End-users are the people whose jobs need access to the database for que

Log based recovery, Log based recovery: Let us first describe the term tran...

Log based recovery: Let us first describe the term transaction log in the context of DBMS. A transaction log is a record in DBMS that remains track of all the transactions of a dat

Define tables students and teachers as sub tables of people, Write a query ...

Write a query to define tables students and teachers as sub tables of people? Create table students of student under people Create table teachers of teacher under people

What function divides one numeric expression, What function divides one num...

What function divides one numeric expression by another and returns the remainder? MOD function divides one numeric expression by another and returns the remainder.

Query by example, Illustrate how you can use QBE to perform logical AND and...

Illustrate how you can use QBE to perform logical AND and OR operation

Which is a valid sql type, Which is a valid SQL type? A valid SQL Shoul...

Which is a valid SQL type? A valid SQL Should be in CHARACTER it is should be NUMERIC and FLOAT.

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