MySQL 8.0

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CREATE TABLE Test(AA varchar(20),BB varchar(20),CC varchar(20),DD integer,EE integer);
insert into Test values ('201902','X','1000',1,1);
insert into Test values ('201902','X','1000',2,2);
insert into Test values ('201902','X','1001',4,3);
insert into Test values ('201902','Y','2000',6,4);
insert into Test values ('201902','Y','2001',8,5);
insert into Test values ('201903','Y','2002',10,6);
insert into Test values ('201904','Y','2002',12,7);
select * 
from Test
where 1=1
order by AA,BB;


AA
BB
CC
DD
EE


201902
X
1000
1
1

201902
X
1000
2
2

201902
X
1001
4
3

201902
Y
2000
6
4

201902
Y
2001
8
5

201903
Y
2002
10
6

201904
Y
2002
12
7


select AA,BB,SUM(DD) AS DD
From (
select AA,BB,CC,DD,ROW_NUMBER() OVER (PARTITION BY AA,BB,CC ORDER BY EE desc) AS KK
from Test) AS SS
Where KK = 1
Group By AA,BB


AA
BB
DD


201902
X
6

201902
Y
14

201903
Y
10

201904
Y
12

AA	BB	CC	DD	EE
201902	X	1000	1	1
201902	X	1000	2	2
201902	X	1001	4	3
201902	Y	2000	6	4
201902	Y	2001	8	5
201903	Y	2002	10	6
201904	Y	2002	12	7