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 the role of order by clause, What is the role of ORDER By Clause? ...

What is the role of ORDER By Clause? ORDER BY clause: The ORDER BY clause permits you to sort the records in your result set. The ORDER BY clause can just be used in select s

Guidelines for creation of table, Guidelines for creation of table: ...

Guidelines for creation of table: Table name should begin with an alphabet. In table name, single quotes and blank spaces are not allowed. Reserve words of that DBM

What features relational dbms contribute level of integrity, A well-maintai...

A well-maintained relational DBMS has a high level of data integrity. What features of a relational DBMS contribute towards this level of integrity? Relational DBMS gives high

Approachs of database management system, The Database Approach In ord...

The Database Approach In order to overcome the limits of a file system, a new approach was needed. Hence a database approach emerged. A database is a persistent collection of

Determine the minimal set of functional dependencies, Determine the minimal...

Determine the minimal set of functional dependencies for the following data. This table is part of the OHSU database of extracurricular activities and tracks the DMICE band's co

How to apply the bcnf decomposition , Consider the following relational sch...

Consider the following relational scheme: R (a,b,c,d,e,f) and its corresponding set of FDs {d→ a, be → c, ac → e, b → f, f → d, a → c}. a. Is the following decomposition i) non

What do you mean by correlated subquery, What do you mean by Correlated sub...

What do you mean by Correlated subquery? Subqueries, or nested queries, are used to bring back a set of rows to be used by the parent query. Depending on how the subquery is writ

Describe the storage structure of indexed sequential files, Describe the st...

Describe the storage structure of indexed sequential files and their access method.  Ans:   Storage structure of Indexed Sequential files and their access: To achieve fast rand

Relationship, What is multiple relationship ?

What is multiple relationship ?

Explain transaction, What is transaction? Collections of operations tha...

What is transaction? Collections of operations that form a single logical unit of work are known as transactions.

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