Chapter 7, Problem 10TD

Program Plan Intro

ALTER TABLE Statement:

• “ALTER TABLE” statement comes under Data Definition Language.
• It is used to modify column, add constraints, add column(s), drop column, rename column name and table name, drop constraints, and so on.

Syntax:

The Syntax to drop constraint is as follows:

ALTER TABLE table_Name ADD CONSTRAINT constraint_Name;

Check:

The check constraint is used to limit the range of values placed in a column. It can be included either with the “CREATE TABLE” or “ALTER TABLE” commands.