Question

Say we have a table

table posts
+---------+-----------+--------------------------------+
| postId  | title     | status    | bodyText           |
+---------+-----------+--------------------------------+
|   1     | Hello!    | deleted   | A deleted post!    |
|   2     | Hello 2!  | deleted   | Another one!       |
|   3     | New 1     | new       | A new one!         |
|   4     | New 2     | new       | A new one again!   |

Can we, in SQL, retrieve a concatenation of a field across rows, by issuing a single query, not having to do the join up in a loop in our back-end code?

Something like

select title from posts group by status ;

Should give a result like

+---------+--------------------+
| deleted | Hello!, Hello 2!   |
| new     | New 1, New 2       |

Answer 1

If you use MySQL then you can use GROUP_CONCAT:

SELECT status, GROUP_CONCAT(title)
FROM posts
GROUP BY status