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CREATE TABLE
INSERT 0 9
| id | title | content | parent_id |
|---|---|---|---|
| 1 | One | First thread main post | null |
| 2 | Two | First thread reply | 1 |
| 3 | Three | First thread reply | 2 |
| 4 | Four | Second thread main post | null |
| 5 | Five | Second thread reply | 4 |
| 6 | Six | Second thread reply | 5 |
| 7 | Six | Second thread reply | 6 |
| 8 | Six | Second thread reply | 7 |
| 9 | Six | Second thread reply | 8 |
SELECT 9
| id | title | content | parent_id |
|---|---|---|---|
| 4 | Four | Second thread main post | null |
SELECT 1