Tamil Nadu Board of Secondary EducationHSC Science Class 12

Write a short note on Primary key constraints. - Computer Science

Advertisements
Advertisements
Short Note

Write a short note on Primary key constraints.

Advertisements

Solution

Primary Constraint:

  • Primly Constraint declares a field as a Primary key which helps to uniquely identify a recor<}ll
  • Primary Constraint is similar to a unique constraint except that only one field of a table can be set as the primary key.
  • The primary key does not allow NULL values and therefore a field declared as the primary key must have the NOT NULL constraint.
Concept: SQL Commands and Their Functions
  Is there an error in this question or solution?
Chapter 12: Structured Query Language (SQL) - Evaluation [Page 231]

APPEARS IN

Tamil Nadu Board Samacheer Kalvi Class 12th Computer Science Answers Guide
Chapter 12 Structured Query Language (SQL)
Evaluation | Q 1. b. | Page 231
Share
Notifications



      Forgot password?
Use app×