表有a, b, c三个字段,数据如下:A B C
---------------
A A 1
A B 2
B A 3
B A 4要求对a, b字段分组,对c求和,实现如下效果:序号 A B C
-------------------
1 A A 1
2 A B 2
1 B A 7上面的序号(流水号)怎么实现,用一句sql?
---------------
A A 1
A B 2
B A 3
B A 4要求对a, b字段分组,对c求和,实现如下效果:序号 A B C
-------------------
1 A A 1
2 A B 2
1 B A 7上面的序号(流水号)怎么实现,用一句sql?
(select a,b,sum(c) c from t2 group by a,b) t
1 a a 1
2 a b 2
3 b a 7
SELECT A,B,SUM(C) C FROM (
SELECT 'A' A,'A' B,1 C FROM DUAL
UNION
SELECT 'A' A,'B' B,2 C FROM DUAL
UNION
SELECT 'B' A,'A' B,3 C FROM DUAL
UNION
SELECT 'B' A,'A' B,4 C FROM DUAL)
GROUP BY A,B
)T
from t2 group by a,b