Define functional and multivalued dependencies, Database Management System

Assignment Help:

Define functional and multivalued dependencies.      

Ans:  A functional dependency is a assets of the semantics of the attributes in a relation. The semantics point out how attributes relate to one another, and identify the functional dependencies between attributes. While a functional dependency is available, the dependency is fixed as a constraint among the attributes. Refer a relation with attributes A and B, in which attribute B is functionally dependent on attribute A. If we know the value of A and we inspect the relation that holds this dependency, we will find out just only one value of B in all of the tuples which have a given value of A, at any moment in time. Note though, that for a given value of B there may be various different values of A. 

Multivalued Dependencies:  A multivalued dependency is an outcome of two independent 1: N relationships A: B and A: C being mixed in similar relation R(A,B,C)


Related Discussions:- Define functional and multivalued dependencies

What is a dataset, What is a dataset? A dataset is an in-memory databas...

What is a dataset? A dataset is an in-memory database that is disconnected from any regular database, but has all the significant characteristics of a regular database. Dataset

Derived horizontal fragmentation, Derived horizontal fragmentation: Some ap...

Derived horizontal fragmentation: Some applications may include a join of two or more relations. If the relations are stored at dissimilar locations, there may be a major overhead

Illustrate the definition of the classes and operation, The definition of t...

The definition of the classes and operation can often be adjusted to increase the amount of inheritance". Justify the above statement.   Adjustment of Inheritance The def

Creating views with read only option-data control, Creating views with Read...

Creating views with Read only option : In the view definition this option is used to make sure that no DML operations can be done on the view.

How many types of users works on database, How many types of users works on...

How many types of users works on database? Users are differentiated through the way they expect to interact along with the system (i) Application programmers-interact with

Dml precompiler in database management system, DML Precompiler All th...

DML Precompiler All the DBMS have two basic sets of Languages - Data Definition Language (DDL) that have the set of commands needed to define the format of the data that is b

Datawarehouse, How to define a job scheduling strategy that will meet busin...

How to define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a

What is a transaction, What is a Transaction? A transaction is an even...

What is a Transaction? A transaction is an event which happens on the database. Generally a transaction reads a value from the database or writes a value to the database. If y

Create a database, Project: Microsoft Access You have been asked by the ...

Project: Microsoft Access You have been asked by the ABC Tanning Salon to create a database that can be used to track the salon's customers.  You are to create a table in Access

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