What is meant by functional dependencies, Database Management System

Assignment Help:

What is meant by functional dependencies?

Consider a relation schema R and α C R and β C R. The functional dependency α ->β  holds on relational schema R if in any legal relation r(R), for all pairs of tuples t1 and t2 in r like t1 [α] =t2 [α], and also t1 [β] =t2 [β].

 


Related Discussions:- What is meant by functional dependencies

advantages of database over file system, Q.   Why would you choose a datab...

Q.   Why would you choose a database system instead of simply storing data in operating system file? Define  at a base concept in details. Sol. Advantages of Database over Fil

Wait-die scheme -deadlock prevention, Wait-die" scheme : The idea is based ...

Wait-die" scheme : The idea is based on non-preventive method. It is based on a simple rule:                                 If Ti requests a database resource that is held by T

Types of locks, Types of Locks There are two necessary types of locks: ...

Types of Locks There are two necessary types of locks: Binary lock : This locking mechanism has two states for to a data item: locked or unlocked Multiple-mode loc

Construct an er diagram for a hospital, Construct an ER diagram for a hospi...

Construct an ER diagram for a hospital along with a set of patients and a set of medical doctors Associate with every patient a log of the several tests and examinations conducted.

Hass, waht is a repeating group?

waht is a repeating group?

Concatenation operator-data manipulation language, Concatenation operator ...

Concatenation operator Example : Printing name and job as one string as column name employees: SELECT ENAME||JOB "EMPLOYEES" FROM EMP;

What are the reasons of bucket overflow, What are the reasons of bucket ove...

What are the reasons of bucket overflow? Explain any two methods for solving this problem. Ans:  It is general for file structures to be divided into equal-length partitions, k

Differentiate between procedural and non procedural language, Differentiate...

Differentiate between Procedural and non procedural languages ? Procedural and non procedural languages - A procedural language specifies the operations to be performed on th

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