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 foreign key, Explain Foreign Key? Foreign Key - Let there are...

Explain Foreign Key? Foreign Key - Let there are two relations (tables) R and S. Any candidate key of the relation R that is referred within the relation S is known as the fo

What is called bit-level striping, Normal 0 false false fal...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Define database management system, Define database management system? D...

Define database management system? Database management system (DBMS) is a set of interrelated data and a combination of programs to access those data.

Database application development, The database application project (DAP) fo...

The database application project (DAP) for this assignment consists of the creation of a fully functional Microsoft Access database application for a real client. I recommend you s

Explain the ansi -sparc schema architecture, (a) Differentiate between info...

(a) Differentiate between information and data . (b) List and briefly explain five potential benefits of the database approach compared to conventional file systems. (c) Diff

Define the normalisation form, Define in which normalisation form if an att...

Define in which normalisation form if an attribute of a composite key is dependent on an attribute of other composite key. Ans: 3NF A relation is in 3 NF if an attribute of

Eliminate redundant data, Eliminate Redundant Data In the "Database Rel...

Eliminate Redundant Data In the "Database Relation" above, the primary key is made up of the D-ID and the Emp-ID. The database-name relies only on the D-ID. The similar databas

What are the two methods for dealing deadlock problem, What are the two met...

What are the two methods for dealing deadlock problem? The two procedures for dealing deadlock problem is deadlock detection and deadlock recovery.

Attribute, a set of possible data value of an attribute is called??

a set of possible data value of an attribute is called??

What is meant by heuristic optimisation, What is meant by heuristic optimis...

What is meant by heuristic optimisation?Discuss the major heuristics that are applied during query optimisation.

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