Multiple choice

The constraints are

  1. rules to prevent invalid data entry

  2. rules to write programs in SQL

  3. rules to create user-defined data type in SQL

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Constraints in SQL are rules enforced on table columns to ensure data integrity and prevent invalid data entry. Common constraints include PRIMARY KEY, FOREIGN KEY, UNIQUE, NOT NULL, and CHECK. They are not used for writing programs or creating data types.

Keep practicing — related questions