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| id | name | start | end | count |
|---|---|---|---|---|
| 1 | A | 2018-12-10 | 2018-12-20 | 34 |
| 2 | B | 2018-12-15 | 2018-12-27 | 19 |
| 3 | C | 2018-12-16 | 2018-12-20 | 56 |
| 4 | D | 2018-12-25 | 2018-12-30 | 43 |
SELECT 4
| acts | sum | start | end |
|---|---|---|---|
| {B,D} | 62 | 2018-12-15 | 2018-12-30 |
| {A,B,C} | 109 | 2018-12-10 | 2018-12-27 |
| {A,B} | 53 | 2018-12-10 | 2018-12-27 |
SELECT 3