在SQL中按组计算移动平均数

Posted 2021-04-05

使用SQL，我可以计算出这样的移动平均线

SELECT id,date,var,AVG(var) OVER (ORDER BY  UNIX_DATE(DATE(date)) RANGE BETWEEN 6 PRECEDING AND CURRENT ROW) AS var_mov_avg_7d
FROM table_name
WHERE id LIKE '2001'

但是，我怎样才能对表中的所有id分别进行计算呢？

答案

你想要的是 partition by:

SELECT id,date,var,
       AVG(var) OVER (PARTITION BY id 
                      ORDER BY UNIX_DATE(DATE(date))
                      RANGE BETWEEN 6 PRECEDING AND CURRENT ROW
                     ) AS var_mov_avg_7d
FROM table_name;