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

Create the table, Question: Using the data model express the following ...

Question: Using the data model express the following queries in SQL. (a) Create the Table named "Cinema" and make the cinema_code to be the primary key of the relation and

Issues relating to the design of the physical database files, The issues re...

The issues relating to the Design of the Physical Database Files Physical File is a file as stored on the disk. The major issues relating to physical files are: • Cons

Synonyms, Synonyms It allows short names or alternative names for objects....

Synonyms It allows short names or alternative names for objects. Example : CREATE SYNONYM D30 FOR EMPD30; Now if we give command:

What is the function of sql server agent windows service, What is the funct...

What is the function of SQL Server Agent Windows service? - It's a Windows service that handles tasks scheduled within SQL Server environment. These tasks are also known as job

How many types of locks are there, Depending upon the rules we have found, ...

Depending upon the rules we have found, we can classify the locks into two types. Shared Lock: A transaction might be acquiring shared lock on a data item in order to read it

Index and tree structure, Index And Tree Structure Let us talk about th...

Index And Tree Structure Let us talk about the data structure that is used for creating indexes. Can we use Binary Search Tree (BST) as Indexes? Let us initial reconsider

Unnormalize form, employee(empid,empname,dept,telno,mobno, add,sssno,tinno,...

employee(empid,empname,dept,telno,mobno, add,sssno,tinno,WEdates,WEcomp,WEadd,WEpos,WEres) this is a employee record which is need to be normalize.the WE means work experience

Keys, #questiontypes of keys examples..

#questiontypes of keys examples..

Define signal, Define Signal. It allows methods to respond to events tr...

Define Signal. It allows methods to respond to events triggered by themselves or by other processes. Each signal corresponds to an exacting event. A signal is represented in Sy

SQL, Ask Write the SQL code that will create the table structure for a tabl...

Ask Write the SQL code that will create the table structure for a table named EMP _1. This table is a subset of the EMPLOYEE table. The basic EMP_1 table structure is summarized in

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages