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CREATE TABLE table1 (id int, grp int, `number` int);
INSERT INTO table1 (id, grp, `number`) VALUES (1,1, 10), (2, 1, 10), (3, 1, 10), (4, 2, 30), (5, 3, 20);
SELECT grp, sum(number) as f
FROM table1
GROUP BY grp
| grp | f |
|---|---|
| 1 | 30 |
| 2 | 30 |
| 3 | 20 |
SELECT
sum(number) as f
FROM
table1
| f |
|---|
| 80 |
SELECT sum(`number`) as f
FROM (SELECT DISTINCT `grp`, `number` FROM table1) g
| f |
|---|
| 60 |