【学习记录】【SQL】目标字段的分组后中位数计算

SELECT
	分组字段,
	AVG(目标字段)
FROM(
	SELECT *,
		ROW_NUMBER() OVER(PARTITION BY 分组字段 ORDER BY UNIQUE字段) AS R1,
		ROW_NUMBER() OVER(PARTITION BY 分组字段 ORDER BY UNIQUE字段) AS R2
	FROM TABLE)
WHERE ABS(R1-R2)=1 OR R1=R2
GROUP BY 分组字段