What is the difference between a key and a superkey, Database Management System

Assignment Help:

What is the difference between a key and a superkey?

Key - A key a single attribute or a combination of two or more attributes of an entity set which is used to identify one or more examples (rows) of the set (table). It is a minimal combination of attributes.

Super Key - A super key is a set of one or more attributes in which, taken collectively, permits us to identify uniquely a tuple within the relation.


Related Discussions:- What is the difference between a key and a superkey

Explain the concept of deadlock, Question: In a multi-user database env...

Question: In a multi-user database environment, locking mechanisms can be used to solve the three basic problems of concurrency. On the other hand, however, locking may also le

Php optimization on iis 8, Project Description: We have purchased facebo...

Project Description: We have purchased facebook style chat software which we are using with our site. It is prepared in PHP but the rest of the site is developed asp.net. Iss

Explain dml with some examples, Explain DML with some examples? DML - D...

Explain DML with some examples? DML - Data Manipulation Language: statements used for managing data within schema objects. Some examples: • SELECT - retrieve data from the a da

Explain current page table and shadow page table, Explain current page tabl...

Explain current page table and shadow page table. The key idea behind the shadow paging method is to maintain two page tables during the life of the transaction: the current pa

Unit database integrity, Relations create the database. They must satisfy v...

Relations create the database. They must satisfy various properties, like no duplicate tuples, no ordering of tuples, and atomic attributes, etc. Relations that satisfy these basic

Differentiate between primary and secondary storage, Differentiate between ...

Differentiate between Primary and secondary storage? Primary and secondary storage - Primary storage device stores the data temporarily. Primary storage is commonly used thro

Locks, Locks: Serialisabilty is just a test whether a given interleaved sch...

Locks: Serialisabilty is just a test whether a given interleaved schedule is ok or has a concurrency related trouble. Though, it does not make sure that the interleaved concurrent

Describe association design of an object, Describe association design of an...

Describe association design of an object by giving one suitable example of it. The Design of Associations Associations are "glue" of advanced object oriented analysis and

Define aggregate functions, Define Aggregate functions and what aggregate f...

Define Aggregate functions and what aggregate functions supported by the MySQL To calculate a summary value from a set of individual values and uses one of the functions known

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