解答
218
SQL文(クエリ)
WITH master AS ( SELECT FORMAT_DATETIME("%Y-%m", date_time) AS year_month , SUM(revenue) AS sum_rev FROM sample.sales WHERE FORMAT_DATETIME("%Y", date_time) = "2017" GROUP BY year_month ) SELECT year_month , ROUND(sum_rev / FIRST_VALUE(sum_rev) OVER (ORDER BY year_month), 2) AS change_from_jan FROM master ORDER BY 2 DESC LIMIT 3