WITH
pm as (
SELECT
measured_at today,
lead(measured_at) OVER (
ORDER BY
measured_at asc
) next_day,
pm10,
lead(pm10) OVER (
ORDER BY
measured_at asc
) next_pm10
FROM
measurements
)
SELECT
*
FROM
pm
where
pm10 < next_pm10
현재 행의 다음 행을 가져올 수 있는 윈도우 함수
LEAD(다음값을_가져오고_싶은_컬럼) OVER (ORDER BY 값을_정렬하고_싶은_컬럼명)