Question

Problem: I’d like to combine the results of a subquery as a text field, with the results separated by a comma (or any symbol really), into the results of the main query.

Example:

Table 1:

 +----------+---------+
 |  user_ID | user    |
 +----------+---------+
 |        1 |   Smith |
 +----------+---------+
 |        2 |   Jones |
 +----------+---------+

Table 1:

 +----------+---------+
 |  user_ID | roles   |
 +----------+---------+
 |        1 |   Admin |
 +----------+---------+
 |        2 |   Staff |
 +----------+---------+
 |        2 |   Admin |
 +----------+---------+
 |        2 |   Super |
 +----------+---------+
 |        1 |   Other |
 +----------+---------+

So the result would be:

 +----------+---------+----------------------------+
 |  user_ID | user    |   roles                    |
 +----------+---------+----------------------------+
 |        1 |   Smith |    Admin, Other            |
 +----------+---------+----------------------------+
 |        2 |   Jones |    Staff, Admin, Super     |
 +----------+---------+----------------------------+

Any help would be greatly appreciated.

Answer 1

Try this:

select t1.user_id, t1.user, group_concat(t2.roles separator ', ') roles
from t1
join t2 on t1.user_id = t2.user_id
group by t1.user_id, t1.user

Check the GROUP_CONCAT documentation for more info.