PreLab Quiz - DDL and DML Commands

1. Which of the following is a DDL command?

• INSERT
• SELECT
• DELETE
• CREATE

2. Which command is used to remove all rows from a table but keep the structure?

• DELETE
• DROP
• TRUNCATE
• REMOVE

3. Which of the following is used to change the structure of an existing table?

• UPDATE
• ALTER
• INSERT
• MODIFY

4. The command to delete a table permanently is:

• DELETE
• TRUNCATE
• REMOVE
• DROP

5. Which SQL command is used to insert new data into a table?

• INSERT INTO
• ADD ROW
• NEW ENTRY
• APPEND

6. What is the correct command to change a column name in MySQL?

• MODIFY COLUMN
• CHANGE COLUMN
• RENAME COLUMN
• ALTER COLUMN

7. Which of the following statements will add a new column `email` to the `Customers` table?

• ALTER Customers ADD email TEXT;
• ALTER TABLE Customers ADD COLUMN email TEXT;
• MODIFY TABLE Customers ADD email TEXT;
• ADD COLUMN email TO Customers;

8. What does the `CHECK` constraint do in a table definition?

• Prevents duplicates
• Ensures a column has only NOT NULL values
• Ensures values meet a condition
• Limits the number of rows

9. Which of the following DML commands is used to change existing data in a table?

• MODIFY
• ALTER
• UPDATE
• CHANGE

10. What happens when you use `DELETE FROM table_name` without a `WHERE` clause?

• Deletes the table
• Deletes all rows
• Deletes only the first row
• Generates an error