Explain superkey, Database Management System

Assignment Help:

Explain Superkey

Ans: A superkey is described in the relational model of database organization like a set of attributes of a relation variable for which it holds that in all relations assigned to that variable there are no two different tuples (rows) that have similar values for the attributes in this set. Consistently a superkey can as well be defined as a set of attributes of a relvar upon that all attributes of the relvar are functionally dependent.


Related Discussions:- Explain superkey

Describe the four main ways of optimising disk block access, Describe the f...

Describe the four main ways of optimising disk block access. Ans: a. Disk  b. Non-volatile writes buffers c. File organization (Clustering) d. Log-based file system

Function module and a normal abap/4 subroutine, What is the difference betw...

What is the difference between the function module and a normal ABAP/4 subroutine? In contrast to normal subroutines function modules have uniquely exact interface.  Declaring da

Data envelopment analysis , I need a help with my assignment of data envelo...

I need a help with my assignment of data envelopment analysis which is due for submission next week on monday the 10th Dec. Will you be able to help so that I can submit it on tim

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

Database, why are older data models are being replaced by new data models

why are older data models are being replaced by new data models

What was the method in which records are physically stored, What was the me...

What was the method in which records are physically stored in a specified order according to a key field in each record ? A method in which records are physically stored within

Queries, Write a query that display ename annual salary and comm from emp t...

Write a query that display ename annual salary and comm from emp table

Views, what is view?explain

what is view?explain

Applications and goals of dbms, What do you mean by DBMS? What is its need ...

What do you mean by DBMS? What is its need and what are its goals. Explain?        OR   Explain Data Base Management System? Sol.  Database management system is a

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