What is functional dependency, Database Management System

Assignment Help:

What is Functional Dependency?

A Functional dependency is shown by X Y among two sets of attributes X and Y that are subsets of R specifies a constraint on the possible tuple that can form a relation state r of R. The constraint is for any two tuples t1 and t2 in r if t1[X] = t2[X] then they have t1[Y] = t2[Y]. This means the value of X component of a tuple uniquely verifies the value of component Y.

 


Related Discussions:- What is functional dependency

Boyce-codd normal form (bcnf), Boyce-Codd Normal Form (BCNF) The relati...

Boyce-Codd Normal Form (BCNF) The relation NEWSTUDENT (Enrolmentno, Sno, Sname, Cname, Cno,) has every attributes participating in candidate keys as all the attributes are assu

Explain the two types of participation constraint., Explain the two types o...

Explain the two types of participation constraint. 1. Total: The participation of an entity set E in a relationship set R is said to be total if each entity in E participates i

Differentiate between a unique key and a primary key, Differentiate between...

Differentiate between a unique key and a primary key. - By default, clustered index on column are created by primary key while nonclustered index are created by unique key.

What is meant by object identifiers, What is meant by object identifiers? ...

What is meant by object identifiers? Object-oriented systems use an object identifier to recognize objects. Object identifiers are unique: that is every object has a single ide

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

Create a view containing name and number of department, Create a view emp_d...

Create a view emp_dep containing e_name and number of dependents from the tables employee and dependent of (i) CREATE VIEW emp_dept AS SELECT ename, COUNT(*) FROM employee, dep

What are the purpose for having variable length records, What are the purpo...

What are the purpose for having variable length records? What kinds of separator characters are required for each? Variable-Length Records - Variable-length records are thos

Bid Cunt, How do I use strap on?#

How do I use strap on?#

Why we use delegation to share implementation, Use Delegation to Share Impl...

Use Delegation to Share Implementation The delegation " Delegation comprises of catching an operation on one object and sending it to other object which is part, or related to

Heuristics, Benefits of using heuristics

Benefits of using heuristics

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