1.company_classifications
----------------------------------------------
company_name | classifications
----------------------------------------------
Company A | 1,2,3
Company B | 1,2


2.classifications
-------------
id | name
-------------
1 | Music
2 | Technologi
3 | Food

Ane butuh query buat result gini :
------------------------------------------------------
company_name | classification_name
------------------------------------------------------
Company A | Music, Technologi, Food
Company B | Music, Food

Sebelumnya sorry,ane tau struktur-nya gak memenuhi 3NF / harus dinormalisasi lg.tapi struktur gitu ane dapet dari client.