Test Your Oracle IS NULL Operator Knowledge

Progress

True / False

In Oracle, the IS NULL operator is used to check if a column contains a NULL value.

True False

The IS NULL operator checks whether a column contains a NULL value.

True / False

The IS NULL operator can be used in the WHERE clause of an Oracle SQL query.

True False

The IS NULL operator is often used in the WHERE clause to filter rows where a column has a NULL value.

True / False

In Oracle, a column defined with a NOT NULL constraint can contain NULL values.

True False

A column defined with a NOT NULL constraint cannot contain NULL values.

True / False

In Oracle, you can use the IS NULL operator with any data type, including numeric, character, and date types.

True False

The IS NULL operator can be used with any data type to check for NULL values.

True / False

The IS NULL operator in Oracle is case-sensitive when used with character data.

True False

The IS NULL operator is not case-sensitive because it checks for the absence of a value, not the value itself.

True / False

In Oracle, you can combine the IS NULL operator with logical operators like AND and OR in the WHERE clause.

True False

The IS NULL operator can be combined with logical operators to form complex conditions in the WHERE clause.

True / False

In Oracle, the IS NULL operator can be used in a CASE statement to handle NULL values.

True False

The IS NULL operator can be used in a CASE statement to handle conditions where a column's value is NULL.

True / False

In Oracle, the IS NULL operator can be used in subqueries to filter rows based on NULL values in the subquery results.

True False

The IS NULL operator can be used in subqueries to filter rows based on whether columns in the subquery contain NULL values.

True / False

Using the IS NULL operator in Oracle with an indexed column will always result in a full table scan.

True False

While checking for NULL values might sometimes lead to a full table scan, if the index is specifically designed to handle NULL values, it can be used to optimize the query.

Q10

True / False

The Oracle Certified Professional (OCP) exam includes knowledge on using the IS NULL operator effectively and understanding its performance implications in SQL queries.

True False

The OCP certification covers advanced topics, including the effective use of the IS NULL operator and understanding its performance implications in SQL queries.

Q11

Single Choice

What is the primary use of the IS NULL operator in Oracle SQL?

To check if a column value is zero To check if a column value is not empty To check if a column value is NULLTo compare two values

The IS NULL operator is used to check if a column contains a NULL value in Oracle.

Q12

Single Choice

Consider the following Oracle SQL query:What will this query return?

SQL Code

SELECT * FROM employees WHERE manager_id IS NULL;

All employees Employees with a NULL value in the manager_id column Employees with a non-NULL value in the manager_id columnAn error because IS NULL cannot be used with manager_id

This query returns rows where the manager_id column contains a NULL value, typically indicating employees who do not have a manager.

Q13

Single Choice

Which of the following statements is true about the IS NULL operator in Oracle?

It can be used with any data type It can only be used with numeric columns It automatically replaces NULL values with zeroIt checks if a column value is empty

The IS NULL operator can be used to check for NULL values in columns of any data type, including strings, numbers, and dates.

Q14

Single Choice

Consider the following Oracle SQL query:What does this query return?

SQL Code

SELECT * FROM orders WHERE shipped_date IS NULL;

Orders with a NULL value in the shipped_date column Orders with a non-NULL value in the shipped_date column Orders with a shipped dateAll orders

This query returns orders where the shipped_date column is NULL, likely indicating that the order has not yet been shipped.

Q15

Single Choice

What will be the result of the following Oracle SQL query?

SQL Code

SELECT * FROM products WHERE price IS NULL ORDER BY product_name;

Products with a non-NULL price Products with a NULL price, sorted by product_name All products sorted by product_nameProducts with a price greater than zero

The IS NULL operator filters the rows to return products with a NULL value in the price column, and the ORDER BY clause sorts the result by product_name.

Q16

Single Choice

Consider the following Oracle SQL query:What does this query return?

SQL Code

SELECT first_name, last_name FROM employees WHERE hire_date IS NULL;

Employees who have not been hired yet Employees hired on the current date Employees with a NULL value in the hire_date columnAll employees

This query returns employees whose hire_date is NULL, which could indicate incomplete or missing data.

Q17

Single Choice

What is the effect of using the IS NOT NULL operator in an Oracle SQL query?

It includes rows where the column value is NULL It excludes rows where the column value is NULL It includes only rows where the column value is zeroIt raises an error if the column contains NULL values

The IS NOT NULL operator filters out rows where the column value is NULL, returning only rows with non-NULL values.

Q18

Single Choice

Consider the following Oracle SQL query:What does this query return?

SQL Code

SELECT * FROM customers WHERE email IS NULL OR phone_number IS NULL;

Customers with either a NULL email or NULL phone number Customers with both email and phone number as NULL Customers with a non-NULL email and phone numberNo customers

The query uses the OR operator to return customers where either the email or phone_number is NULL.

Q19

Single Choice

How does Oracle treat NULL values when using the IS NULL operator in a subquery?

NULL values are always included in the result NULL values are ignored The IS NULL operator can be used to specifically filter NULL values in subqueriesThe query raises an error if NULL values are present

The IS NULL operator can be used within subqueries to specifically target and filter out NULL values.

Q20

Single Choice

In an Oracle certification exam, you encounter the following SQL statement:What does this query return?

SQL Code

SELECT product_id, product_name FROM products WHERE category_id IS NULL AND discontinued IS NULL;

Products that belong to a category and are discontinued Products that do not belong to any category and are not discontinued Products that do not belong to any category and are discontinuedProducts that belong to a category and are not discontinued

This query returns products where both category_id and discontinued are NULL, indicating that these products do not belong to any category and are marked as discontinued.

Q21

Multiple Choice

Which SQL code snippet correctly uses the IS NULL operator to filter employees where the middle name is NULL in Oracle?

SQL Code

SELECT *
FROM employees
WHERE middle_name IS NULL;

SELECT *
FROM employees
WHERE middle_name = NULL;

SELECT employee_id, middle_name
FROM employees
WHERE middle_name IS NULL;

SELECT * FROM employees WHERE middle_name IS NULL; SELECT * FROM employees WHERE middle_name = NULL; SELECT employee_id, middle_name FROM employees WHERE middle_name IS NULL;SELECT * FROM employees WHERE middle_name IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter employees where the middle name is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q22

Multiple Choice

Which SQL code snippet demonstrates how to use the IS NULL operator to filter orders where the delivery date is NULL in Oracle?

SQL Code

SELECT *
FROM orders
WHERE delivery_date IS NULL;

SELECT *
FROM orders
WHERE delivery_date = NULL;

SELECT order_id, delivery_date
FROM orders
WHERE delivery_date IS NULL;

SELECT * FROM orders WHERE delivery_date IS NULL; SELECT * FROM orders WHERE delivery_date = NULL; SELECT order_id, delivery_date FROM orders WHERE delivery_date IS NULL;SELECT * FROM orders WHERE delivery_date IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter orders where the delivery date is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q23

Multiple Choice

Which SQL code snippet uses the IS NULL operator to filter products where the expiration date is NULL in Oracle?

SQL Code

SELECT *
FROM products
WHERE expiration_date IS NULL;

SELECT *
FROM products
WHERE expiration_date = NULL;

SELECT product_id, expiration_date
FROM products
WHERE expiration_date IS NULL;

SELECT * FROM products WHERE expiration_date IS NULL; SELECT * FROM products WHERE expiration_date = NULL; SELECT product_id, expiration_date FROM products WHERE expiration_date IS NULL;SELECT * FROM products WHERE expiration_date IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter products where the expiration date is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q24

Multiple Choice

Which SQL code snippet demonstrates how to use the IS NULL operator to filter customers where the phone number is NULL in Oracle?

SQL Code

SELECT *
FROM customers
WHERE phone_number IS NULL;

SELECT *
FROM customers
WHERE phone_number = NULL;

SELECT customer_id, phone_number
FROM customers
WHERE phone_number IS NULL;

SELECT * FROM customers WHERE phone_number IS NULL; SELECT * FROM customers WHERE phone_number = NULL; SELECT customer_id, phone_number FROM customers WHERE phone_number IS NULL;SELECT * FROM customers WHERE phone_number IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter customers where the phone number is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q25

Multiple Choice

Which SQL code snippet uses the IS NULL operator to filter inventory items where the stock quantity is NULL in Oracle?

SQL Code

SELECT *
FROM inventory
WHERE stock_quantity IS NULL;

SELECT *
FROM inventory
WHERE stock_quantity = NULL;

SELECT item_id, stock_quantity
FROM inventory
WHERE stock_quantity IS NULL;

SELECT * FROM inventory WHERE stock_quantity IS NULL; SELECT * FROM inventory WHERE stock_quantity = NULL; SELECT item_id, stock_quantity FROM inventory WHERE stock_quantity IS NULL;SELECT * FROM inventory WHERE stock_quantity IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter inventory items where the stock quantity is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q26

Multiple Choice

Which SQL code snippet demonstrates advanced use of the IS NULL operator to filter sales records where the discount is NULL in Oracle?

SQL Code

SELECT *
FROM sales
WHERE discount IS NULL;

SELECT *
FROM sales
WHERE discount = NULL;

SELECT sale_id, discount
FROM sales
WHERE discount IS NULL;

SELECT * FROM sales WHERE discount IS NULL; SELECT * FROM sales WHERE discount = NULL; SELECT sale_id, discount FROM sales WHERE discount IS NULL;SELECT * FROM sales WHERE discount IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter sales records where the discount is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q27

Multiple Choice

Which SQL code snippet uses the IS NULL operator to filter employees where the email address is NULL in Oracle?

SQL Code

SELECT *
FROM employees
WHERE email IS NULL;

SELECT *
FROM employees
WHERE email = NULL;

SELECT employee_id, email
FROM employees
WHERE email IS NULL;

SELECT * FROM employees WHERE email IS NULL; SELECT * FROM employees WHERE email = NULL; SELECT employee_id, email FROM employees WHERE email IS NULL;SELECT * FROM employees WHERE email IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter employees where the email address is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q28

Multiple Choice

Which SQL code snippet demonstrates advanced use of the IS NULL operator to filter order items where the shipping weight is NULL in Oracle?

SQL Code

SELECT *
FROM order_items
WHERE shipping_weight IS NULL;

SELECT *
FROM order_items
WHERE shipping_weight = NULL;

SELECT item_id, shipping_weight
FROM order_items
WHERE shipping_weight IS NULL;

SELECT * FROM order_items WHERE shipping_weight IS NULL; SELECT * FROM order_items WHERE shipping_weight = NULL; SELECT item_id, shipping_weight FROM order_items WHERE shipping_weight IS NULL;SELECT * FROM order_items WHERE shipping_weight IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter order items where the shipping weight is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q29

Multiple Choice

Which SQL code snippet uses the IS NULL operator to filter departments where the department manager is NULL in Oracle?

SQL Code

SELECT *
FROM departments
WHERE manager_id IS NULL;

SELECT *
FROM departments
WHERE manager_id = NULL;

SELECT department_id, manager_id
FROM departments
WHERE manager_id IS NULL;

SELECT * FROM departments WHERE manager_id IS NULL; SELECT * FROM departments WHERE manager_id = NULL; SELECT department_id, manager_id FROM departments WHERE manager_id IS NULL;SELECT * FROM departments WHERE manager_id IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter departments where the department manager is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Q30

Multiple Choice

Which SQL code snippet demonstrates the certification-level use of the IS NULL operator to filter orders where the payment date is NULL in Oracle?

SQL Code

SELECT *
FROM orders
WHERE payment_date IS NULL;

SELECT *
FROM orders
WHERE payment_date = NULL;

SELECT order_id, payment_date
FROM orders
WHERE payment_date IS NULL;

SELECT * FROM orders WHERE payment_date IS NULL; SELECT * FROM orders WHERE payment_date = NULL; SELECT order_id, payment_date FROM orders WHERE payment_date IS NULL;SELECT * FROM orders WHERE payment_date IS NOT NULL;

Options A and C correctly use the IS NULL operator to filter orders where the payment date is NULL. Option B incorrectly uses the equality operator instead of IS NULL.

Oracle Database Quiz Questions