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CREATE TABLE
INSERT 0 4
| room_id | time_start | time_end |
|---|---|---|
| 1 | 07:00:00 | 07:30:00 |
| 1 | 08:30:00 | 09:30:00 |
| 2 | 07:30:00 | 08:15:00 |
| 2 | 10:15:00 | 11:20:00 |
SELECT 4
| free_time_start | free_time_end | ?column? |
|---|---|---|
| 07:31:00 | 08:29:00 | t |
SELECT 1