NTILE

1
SELECT
2
  name,
3
  salary,
4
  NTILE(4) OVER (ORDER BY salary) as quartile
5
FROM employees;

1
SELECT
2
  customer_id,
3
  total_spending,
4
  NTILE(10) OVER (ORDER BY total_spending DESC) as spending_decile
5
FROM customer_spending;

1
SELECT
2
  category,
3
  product_name,
4
  price,
5
  NTILE(4) OVER (PARTITION BY category ORDER BY price) as price_quartile
6
FROM products;

1
SELECT *
2
FROM (
3
  SELECT
4
    *,
5
    NTILE(10) OVER (ORDER BY score DESC) as decile
6
  FROM students
7
) sub
8
WHERE decile = 1;