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

Give two profit of reuse of code, Give two profit of Reuse of Code. Re...

Give two profit of Reuse of Code. Reusing the implementation . Place existing class directly inside a new class. The new class can be made up of any number and type of the oth

ER diagram, construct an er diagram for a hospital with a set of patients a...

construct an er diagram for a hospital with a set of patients and a set of medical doctors. associate with each patient a log of various test and examination conducted.convert er d

Draw and explain the three level architecture of database, Draw and explain...

Draw and explain the three level architecture of the database system? A DBMS gives three levels of data is said to follow three-level architecture. The trget of the three-schem

Explain the utilities which help the dba to manage database, Explain the ut...

Explain the utilities which help the DBA to manage the database? Every DBA uses database utilities to maintain and control their databases. But there is a lot of confusion wit

Physical datastructure, what is physical data structure

what is physical data structure

Answer, Describe multi key files

Describe multi key files

How do you find the final model after iterative analysis, How do you find t...

How do you find the final model after iterative analysis? Why is iterative analysis of any of the problem needed? The final model serves as the base for system architectur

Explain physical and logical independence, Define Physical and Logical inde...

Define Physical and Logical independence Ans: Physical data independence: The ability to modify physical level without causing application program to be rewritten. Logic

Describe the algorithm for updating indices, Describe the algorithm for upd...

Describe the algorithm for updating indices for a single level index when a record is (i) Inserted (ii) deleted What will be the modification if there are multilevel in

Define view? how it is related to data independence, A View may be defi...

A View may be defined of as a virtual table, that is, a table that does not really exist in its own right but is instead inferred from one or more underlying base data table. T

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages