Day 13 — DDL (Data Definition Language)

What is DDL in SAP HANA? Explain the commonly used DDL commands.

DDL (Data Definition Language) is used to create and manage database objects such as tables, views, schemas, and indexes. 1. What is DDL? a. Used to define database structure. b. Creates new database objects. c. Modifies existing database objects. d. Deletes database objects. e. Used during database design and development. 2. Common DDL Commands a. CREATE – Creates a new object. b. ALTER – Modifies an existing object. c. DROP – Deletes an object permanently. d. TRUNCATE – Removes all records from a table. e. RENAME – Changes the object name. 3. Why Do We Use DDL? a. Create new tables. b. Add new columns. c. Remove unwanted tables. d. Change table structure. e. Maintain database objects.

• A company starts a new HR project. • The developer creates an EMPLOYEE table. • Later, a Salary column is added. • An old temporary table is deleted. • All these activities are performed using DDL commands.

1. What is DDL? 2. Name five DDL commands. 3. What is the purpose of CREATE? 4. What is the difference between DROP and TRUNCATE? 5. Give one real-time example of DDL.