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

Data base design, how to design a bakery business in data base

how to design a bakery business in data base

Which operations need the participating relations to union, Which operation...

Which operations need the participating relations to be union compatible? A UNION, INTERSECTION and DIFFERENCE operations need the participating relations to be union compatibl

Union - basic set operation, UNION If R1 and R2 are two union compatibl...

UNION If R1 and R2 are two union compatible relations then R3 = R1 ∪ R2 is the relation having tuples that are either in R1 or in R2 or in both. In case, R3 will have tuples

Describe logical data independence, Describe logical data independence ? ...

Describe logical data independence ? Logical Data Independence - It is the capacity to modify the conceptual schema without having to change external schemas or application p

Outer join, Outer Join: The use of Outer Join is that it still joins those...

Outer Join: The use of Outer Join is that it still joins those tuples that do not have matching values in common columns are also contained in the result table. Outer join places

Data base design for a museum information system, In this practical assignm...

In this practical assignment, we will run through a complete database application development cycle, starting with the schema design, from an initial data import to database applic

Which types of data supported by mysql, Which types of data supported by My...

Which types of data supported by MySQL for Time and Date formats?  MySQL supports a number of time and date column formats: Some of them are 1) DATE 2) DATETIME 3) TIM

Seeking hr searcher, Project Description: The work is about founding the...

Project Description: The work is about founding the best skilled person for the job. I will give you the job description. Skills required are Data Entry, Database Administrat

Define the terms ddl and dml, Define the terms i) DDL ii) DML DDL: Data...

Define the terms i) DDL ii) DML DDL: Data base schema is particular by a set of definitions expressed by a special language known as a data definition language. DML: A data

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