Credo che questo sia quello che stai cercando, o che potrebbe farti iniziare:
SELECT
t.therapist_name,
dl.day,
GROUP_CONCAT(DISTINCT dl.name SEPARATOR ',') AS locations
FROM
therapists t
LEFT JOIN days_location dl ON dl.therapist_id = t.id
LEFT JOIN location l ON dl.location_id = l.id
GROUP BY t.therapist_name, dl.day
Per therapists.id = 1 questo dovrebbe darti risultati:
+----------------+-----------+-----------------------+
| therapist_name | day | locations |
+----------------+-----------+-----------------------+
| Therapist 1 | monday | Location 1,Location 2 |
| Therapist 1 | wednesday | Location 3 |
| Therapist 1 | friday | Location 1 |
+----------------+-----------+-----------------------+
Se devi concatenare day con locations colonna quindi usa un semplice CONCAT() :
SELECT
therapist_name,
CONCAT(day, '(', locations, ')') AS locations
FROM (
SELECT
t.therapist_name,
dl.day,
GROUP_CONCAT(DISTINCT dl.name SEPARATOR ',') AS locations
FROM
therapists t
LEFT JOIN days_location dl ON dl.therapist_id = t.id
LEFT JOIN location l ON dl.location_id = l.id
GROUP BY t.therapist_name, dl.day
) t
GROUP BY therapist_name, locations
L'output dovrebbe essere simile a:
+----------------+-------------------------------+
| therapist_name | locations |
+----------------+-------------------------------+
| Therapist 1 | monday(Location 1,Location 2) |
| Therapist 1 | wednesday(Location 3) |
| Therapist 1 | friday(Location 1) |
+----------------+-------------------------------+
Se hai bisogno di raggruppare tutto in una riga per ogni terapista, puoi GROUP_CONCAT() di nuovo.
Modifica dopo i commenti :
SELECT
therapist_name,
GROUP_CONCAT( CONCAT(day, '(', locations, ')') SEPARATOR ',' ) AS locations
FROM (
SELECT
t.therapist_name,
dl.day,
GROUP_CONCAT(DISTINCT dl.name SEPARATOR ',') AS locations
FROM
therapists t
LEFT JOIN days_location dl ON dl.therapist_id = t.id
LEFT JOIN location l ON dl.location_id = l.id
GROUP BY t.therapist_name, dl.day
) t
GROUP BY therapist_name
Non ho testato il codice, quindi potrebbero esserci alcuni piccoli errori da modificare. Non c'è modo di testarlo atm.
