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| date1 | date2 | date3 | max_date |
|---|---|---|---|
| 2019-01-01 | 2019-01-20 | 2019-02-10 | 2019-02-10 |
| null | null | 2019-02-01 | 2019-02-01 |
| null | 2019-02-01 | 2019-02-02 | 2019-02-02 |
Warning: Null value is eliminated by an aggregate or other SET operation.