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| id | user_id | note_id | subject_name | count(subject_name COLLATE utf8mb4_bin) over (partition by user_id, subject_name COLLATE utf8mb4_bin) |
|---|---|---|---|---|
| 10 | 2 | UdMs870BSswp | CN | 2 |
| 12 | 2 | 8stMvslwIGr2 | CN | 2 |
| 13 | 2 | PB3KNbbFkaUm | cn | 1 |