GroupBy ID but keep multiple values - mysql

Question

I have the following MySQL table:
+----------+----------+---------+-------------+------------+----------+----------+-----------+
| queue_id | email_id | user_id | customer_id | send_date | campaign | approved | scheduled |
+----------+----------+---------+-------------+------------+----------+----------+-----------+
| 1 | 1 | 1 | 1 | 2018-10-30 | 1 | 1 | 1 |
| 2 | 1 | 2 | 1 | 2018-10-30 | 1 | 1 | 1 |
| 3 | 2 | 1 | 1 | 2018-11-02 | 1 | 1 | 1 |
| 4 | 2 | 2 | 1 | 2018-11-02 | 1 | 0 | 1 |
| 5 | 2 | 3 | 1 | 2018-11-02 | 1 | 1 | 1 |
+----------+----------+---------+-------------+------------+----------+----------+-----------+
Where the email_id, user_id, and customer_id are all foreign keys.
What I need to do is return the send_date, subject (which is apart of the email table that the email_id references), and name (which is apart of the business table that the user_id references) but only for columns where the approved column is true. The idea is to ultimately display the data to a user in an HTML table where the table would look like the following (using the sample data provided):
+--------------------+--------------------------+---------------+
| October 30th, 2018 | Subject for email_id "1" | View Approved |
| November 2nd, 2018 | Subject for email_id "2" | View Approved |
+--------------------+--------------------------+---------------+
Whenever the user would click on the "View Approved" cell, then it would display all of the business names that approved that particular email.
I tried using the following query, but it is only returning one value in the name column:
SELECT
DATE_FORMAT(q.`send_date`, "%M %D, %Y") AS `date_visited`,
e.`subject`,
b.`name`
FROM
`email_queue` AS q
INNER JOIN
`email` AS e ON q.`email_id` = e.`email_id`
INNER JOIN
`user` AS u ON q.`user_id` = u.`user_id`
INNER JOIN
`business` AS b ON u.`business_id` = b.`business_id`
WHERE
q.`approved` = true
GROUP BY
e.`email_id`
ORDER BY
q.`send_date` DESC
How can I structure my query to where it would return all of the business names in the name column instead of just one?

Answer 1

You can get all the unqiue business names in a Comma separated string, using Group_Concat() function with Distinct clause.
Try:
GROUP_CONCAT(DISTINCT b.`name` SEPARATOR ',') AS name
instead of:
b.`name`
Note:
You can avoid the usage of Distinct clause, if there would not be any duplicate user_id (for a specific email_id), thus ensuring that b.name is also unique.
You can also use any separator, instead of comma. For eg: to use separator as pipe character |, you would write the query as:
GROUP_CONCAT(DISTINCT b.nameSEPARATOR '|') AS name