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| subject | GROUP_CONCAT(t2.subject) |
|---|---|
| 101,102 | subject 1,subject 2 |
| 103,105 | subject 3,subject 5 |
| 104 | subject 4 |
| subject | GROUP_CONCAT(t2.subject) |
|---|---|
| 101,102 | subject 1,subject 2 |
| 103,105 | subject 3,subject 5 |
| 104 | subject 4 |