SELECT COUNT(*) AS total_employees
FROM employees;

Answer 2

SELECT AVG(salary) AS average_salary
FROM employees;

Answer 3

SELECT MAX(price) AS highest_price
FROM products;

Answer 4

SELECT MIN(price) AS lowest_price
FROM products;

Answer 5

SELECT
    SUM(amount) AS total_revenue
FROM orders
WHERE order_status = 'Completed';

Answer 6

SELECT
    COUNT(DISTINCT customer_id) AS unique_customers
FROM orders;

Answer 7

SELECT
    MAX(amount) AS largest_order
FROM orders;

Answer 8

SELECT
    AVG(amount) AS average_order_value
FROM orders
WHERE order_status = 'Completed';

Answer 9

SELECT
    COUNT(*) AS completed_orders
FROM orders
WHERE order_status = 'Completed';

Answer 10

SELECT
    SUM(amount) AS total_revenue,
    COUNT(DISTINCT customer_id) AS unique_customers
FROM orders
WHERE order_status = 'Completed';

🔥 Mini Challenge

You have an orders table: order_id | customer_id | amount | status

Business requirement: Calculate: Total completed orders, Unique completed customers, Total completed revenue, Average completed order value, Largest completed order

Solution

SELECT
    COUNT(*) AS completed_orders,
    COUNT(DISTINCT customer_id) AS unique_customers,
    SUM(amount) AS total_revenue,
    AVG(amount) AS average_order_value,
    MAX(amount) AS largest_order
FROM orders
WHERE status = 'Completed';

Expected result: completed_orders = 4, unique_customers = 3, total_revenue = 15500, average_order_value = 3875, largest_order = 6000

Double Tap ❤️ For Part-6