kheming.sql

SELECT
    id AS client_id,
    (SELECT COUNT(*) FROM orders o1 WHERE o1.client_id = c.id AND o1.price < 1000) AS count1,
    (SELECT COUNT(*) FROM orders o2 WHERE o2.client_id = c.id AND o2.price > 1000) AS count2
    FROM clients c

SELECT c.* FROM (
  SELECT *,
  row_number() OVER (PARTITION BY client_id) AS num
  FROM orders
) as c WHERE c.num % 3 = 0

SELECT c.* FROM (
  SELECT *,
  row_number() OVER (PARTITION BY client_id) AS num
  FROM orders
  WHERE price > 1000
) as c WHERE c.num % 3 = 0