MySQL 8.0

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create table yourtable (yourdate date, yourvalue int);
insert into yourtable values (now(), 200);
insert into yourtable values (DATE_ADD(now(), INTERVAL 5 DAY) , 100);
insert into yourtable values (DATE_ADD(now(), INTERVAL -40 DAY) , 500);
insert into yourtable values (DATE_ADD(now(), INTERVAL -42 DAY) , 70);
insert into yourtable values (DATE_ADD(now(), INTERVAL -80 DAY) , 20);
insert into yourtable values (DATE_ADD(now(), INTERVAL -75 DAY) , 30);
insert into yourtable values (DATE_ADD(now(), INTERVAL -76 DAY) , -2000);
insert into yourtable values (DATE_ADD(now(), INTERVAL -100 DAY) , 10);
insert into yourtable values (DATE_ADD(now(), INTERVAL -100 DAY) , 1000);
insert into yourtable values (DATE_ADD(now(), INTERVAL -100 DAY) , -1000);
SELECT yourdate, yourvalue FROM yourtable;


yourdate
yourvalue


2023-10-17
200

2023-10-22
100

2023-09-07
500

2023-09-05
70

2023-07-29
20

2023-08-03
30

2023-08-02
-2000

2023-07-09
10

2023-07-09
1000

2023-07-09
-1000


SELECT MONTHNAME(yourdate) AS month, 
MONTH(yourdate) AS monthnr, 
SUM(yourvalue) AS yoursum
FROM yourtable
WHERE yourvalue > 0
GROUP BY MONTHNAME(yourdate), MONTH(yourdate)
ORDER BY MONTH(yourdate);


month
monthnr
yoursum


July
7
1030

August
8
30

September
9
570

October
10
300

yourdate	yourvalue
2023-10-17	200
2023-10-22	100
2023-09-07	500
2023-09-05	70
2023-07-29	20
2023-08-03	30
2023-08-02	-2000
2023-07-09	10
2023-07-09	1000
2023-07-09	-1000