解答
155
SQL文(クエリ)
WITH pref17 AS ( SELECT prefecture FROM sample.sales JOIN sample.customers USING (user_id) WHERE EXTRACT(YEAR FROM date_time) = 2017 GROUP BY prefecture HAVING SUM(revenue) / COUNT(DISTINCT order_id) <= 2000 ) , pref18 AS ( SELECT prefecture FROM sample.sales JOIN sample.customers USING (user_id) WHERE EXTRACT(YEAR FROM date_time) = 2018 GROUP BY prefecture HAVING SUM(revenue) / COUNT(DISTINCT order_id) >= 6000 ) , pref19 AS ( SELECT prefecture FROM sample.sales JOIN sample.customers USING (user_id) WHERE EXTRACT(YEAR FROM date_time) = 2019 GROUP BY prefecture HAVING SUM(revenue) / COUNT(DISTINCT order_id) >= 6000 ) SELECT * FROM pref17 INTERSECT DISTINCT SELECT * FROM pref18 INTERSECT DISTINCT SELECT * FROM pref19