Concatenando Strings GROUP_BY

# Concatenando strings usando "," (virgula) como separador

SELECT tabela1.atributo,GROUP_CONCAT(tabela2.atributo SEPARATOR ',') FROM banco.tabelaN_N INNER JOIN classes ON tabelaN_N.tabela2_id = tabela2.id INNER JOIN tabela1 ON tabela1_id = tabela1.id GROUP BY tabela1.id;