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CREATE TABLE
INSERT 0 6
| event | time | id | user_id |
|---|---|---|---|
| a | 2021-08-09 11:00:00 | 1 | 1 |
| a | 2021-08-09 12:00:00 | 2 | 1 |
| b | 2021-08-09 13:00:00 | 3 | 1 |
| a | 2021-08-09 13:30:00 | 4 | 2 |
| b | 2021-08-09 14:00:00 | 5 | 2 |
| b | 2021-08-09 14:10:00 | 6 | 2 |
SELECT 6
| event | time | id | user_id | lag_id |
|---|---|---|---|---|
| a | 2021-08-09 11:00:00 | 1 | 1 | null |
| a | 2021-08-09 12:00:00 | 2 | 1 | null |
| b | 2021-08-09 13:00:00 | 3 | 1 | 2 |
| a | 2021-08-09 13:30:00 | 4 | 2 | null |
| b | 2021-08-09 14:00:00 | 5 | 2 | 4 |
| b | 2021-08-09 14:10:00 | 6 | 2 | 4 |
SELECT 6