my-guitar-shop-database-exersices/How-to-code-subqueries.sql

-- Exercise 1
SELECT DISTINCT category_name
FROM categories
WHERE category_id IN
(SELECT category_id
FROM products)
ORDER BY category_name

-- Exercise 2
SELECT product_name, list_price
FROM products
WHERE list_price >
(SELECT AVG(list_price)
FROM products)
ORDER BY list_price DESC;

-- Exercise 3
SELECT category_name
FROM categories
WHERE NOT EXISTS
(SELECT *
FROM products
WHERE category_id = categories.category_id);

-- Exercise 4
???

-- Exercise 4 Part 2
???

-- Exercise 5
???

-- Exercise 6
???