I ran into some problems while structuring my database, and I will ask questions.
i have a table in database
| id | id_study | writer |
|---|---|---|
| 1 | 1 | writer1 |
| 2 | 1 | writer2 |
| 3 | 2 | writer3 |
how to combine 2 table rows to produce output like below
| id | id_study | writer |
|---|---|---|
| 1,2 | 1 | writer1, writer2 |
| 3 | 2 | writer3 |
CodePudding user response：
SELECT GROUP_CONCAT(id) as id, id_study,GROUP_CONCAT(Writer) as Writer
FROM TABLE
GROUP BY id_study;