×
FREE ASSISTANCE FOR THE INQUISITIVE PEOPLE
Tutorial Topics
X
softetechnologies
CREATE TABLE - Structured Query Language
Alternate keys - RDBMS - SQL
72    Arnab De    21/11/2021   

In a relation or table can have more than one choice of primary key, but only one of them set as a primary key. All the others keys which are able to declared as primary key are called an Alternate Key.  That is all alternate key of a table can uniquely identify every tuple in that relation or table.

Lets consider, a relation called emp

Emp
Emp_SSN Emp_No Emp_Name
1234544434 E-001 Pradipta Pal
5345232444 E-002 Abhijit Ganguly
4645673422 E-003 Suman Banerjee
softetechnologies

In the above table Emp_SSN  and Emp_No both can identify a student uniquely. We can declare those fields as a primary key. That is why those fields are known as alternate keys

softetechnologies
CREATE TABLE - Structured Query Language
softetechnologies
Author Details
Arnab De
I have over 16 years of experience working as an IT professional, ranging from teaching at my own institute to being a computer faculty at different leading institute across Kolkata. I also work as a web developer and designer, having worked for renowned companies and brand. Through tutorialathome, I wish to share my years of knowledge with the readers.
Enter New Comment
Comment History
No Comment Found Yet.
Rabindranath Tagore
Don't limit a child to your own learning, for he was born in another time.
Rabindranath Tagore
1677
25.8
Today So Far
Total View (Lakh)
softetechnologies
01/01/2018     31582
28/06/2017     26609
02/08/2017     23327
26/05/2018     21521
15/05/2017     20221
06/07/2017     19001
01/08/2017     17462
21/04/2018     17234
01/07/2017     14866
25/04/2018     14109
softetechnologies