我有一张桌子
ID REFGROUP YEAR MONTH VALUE
--- ----- ------ ----- -----
1 1000 2018 1 10
2 1000 2018 2 8
3 1000 2018 3 12
4 2000 2018 1 6
5 2000 2018 2 8
6 2000 2018 3 1
我希望按组和年份逐月获得平均值
ID REFGROUP YEAR MONTH VALUE
--- ----- ------ ----- -----
1 1000 2018 1 10
2 1000 2018 2 9
3 1000 2018 3 10
4 2000 2018 1 6
5 2000 2018 2 7
6 2000 2018 3 5
结果将在上面。第二个月,获得前两个月的平均值。第三个月,我将按照refgroup和year获得前三个月的平均值。
我每个月都试过工会但是。它会降低性能。我每年都要做12个月。如何编写SQL查询比我写的更快。我需要8分钟太多了
select 1 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=1 GROUP BY REFGROUP,AYEAR
UNION
select 2 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=2 GROUP BY REFGROUP,AYEAR
UNION
select 3 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=3 GROUP BY REFGROUP,AYEAR
UNION
select 4 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=4 GROUP BY REFGROUP,AYEAR
UNION
select 5 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=5 GROUP BY REFGROUP,AYEAR
UNION
select 6 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=6 GROUP BY REFGROUP,AYEAR
UNION
select 7 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=7 GROUP BY REFGROUP,AYEAR
UNION
select 8 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=8 GROUP BY REFGROUP,AYEAR
UNION
select 9 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=9 GROUP BY REFGROUP,AYEAR
UNION
select 10 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=10 GROUP BY REFGROUP,AYEAR
UNION
select 11 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=11 GROUP BY REFGROUP,AYEAR
UNION
select 12 AS AMONTHH, REFGROUP,AYEAR, AVG(TOTAL) from BMS.FNC_W_PAYROL WHERE AMONTH<=12 GROUP BY REFGROUP,AYEAR
我们可以在这里使用分析函数:
SELECT
ID, REFGROUP, YEAR, MONTH,
AVG(VALUE) OVER (PARTITION BY REFGROUP, YEAR ORDER BY MONTH) AVG_VALUE
FROM yourTable
ORDER BY
REFGROUP, YEAR, MONTH;