Sql server TSQL按计算分组
我用一些数据得到了这张表:Sql server TSQL按计算分组,sql-server,math,group-by,Sql Server,Math,Group By,我用一些数据得到了这张表: SELECT Id, SubId, N1, N2, N3 FROM table1 WHERE Id = 2 Id SubId N1 N2 N3 ----------- -------- ----------- ----------- ---------------------- 2 1 94917 97030 0 2 2
SELECT Id, SubId, N1, N2, N3 FROM table1 WHERE Id = 2
Id SubId N1 N2 N3
----------- -------- ----------- ----------- ----------------------
2 1 94917 97030 0
2 2 35087 41306 0
2 3 189671 194224 0
2 4 44905 46218 0
2 5 65760 70959 0
2 6 620 2395 0
2 7 60336 69531 0
2 8 65517 70666 0
我运行这个查询
UPDATE table1
SET N3 = CASE WHEN N1 = 0 THEN 0 ELSE (( N2 * 1.0 / N1 ) -1) * 100 END
Id SubId N1 N2 N3
----------- -------- ----------- ----------- ----------------------
2 1 94917 97030 2.2261554832
2 2 35087 41306 17.7245133525
2 3 189671 194224 2.4004723969
2 4 44905 46218 2.9239505622
2 5 65760 70959 7.9060218978
2 6 620 2395 286.2903225806
2 7 60336 69531 15.2396579156
2 8 65517 70666 7.8590289543
因此,当我按Id对表进行分组时,我得到了以下数据:
SELECT Id,
SUM(N1) AS N1,
SUM(N2) AS N2,
CAST(0 AS NUMERIC(10,2)) AS N3
INTO table2
FROM table1
GROUP BY Id
UPDATE table2
SET N3 = CASE WHEN N1 = 0 THEN 0 ELSE (( N2 * 1.0 / N1 ) -1) * 100 END
SELECT Id, N1, N2, N3 FROM table2 WHERE Id = 2
Id N1 N2 N3
----------- ----------- ----------- ----------------------
2 556813 592329 6.38
问题是,当我按ID(6.38)分组而不重新计算字段(第二次更新)时,我如何获得相同的N3值,我试图应用反向计算((N3/100)+1)并对N3字段求和,但没有起作用。只需将
N1
和N2
替换为SUM(N1)
和SUM(N2)
SELECT Id,
SUM(N1) AS N1,
SUM(N2) AS N2,
N3 = CAST(CASE WHEN SUM(N1) = 0 THEN 0 ELSE (( SUM(N2) * 1.0 / SUM(N1) ) -1) * 100 END AS NUMERIC(10,2))
FROM table1
GROUP BY Id
演示在
N3需要使用Sum(N1)和Sum(N2)作为值,而不是N1和N2,因为您是基于聚合而不是单个值来计算N3。[offtopic]不应该
来自表2
而应该来自表2
?[/offtopic]
SELECT Id,
SUM(N1) AS N1,
SUM(N2) AS N2,
CAST(CASE WHEN SUM(N1) = 0 THEN 0 ELSE (( SUM(N2) * 1.0 / SUM(N1) ) -1) * 100 END AS NUMERIC(10,2))) as N3
FROM temp
GROUP BY Id