SELECT DISTINCT title FROM vocals AS t1 JOIN songs AS t2 ON t1.songid = t2.songid EXCEPT SELECT t2.title FROM vocals AS t1 JOIN songs AS t2 ON t1.songid = t2.songid WHERE TYPE = "back"
Temukan semua lagu yang tidak memiliki vokal belakang.
CREATE TABLE songs (title VARCHAR, songid VARCHAR); CREATE TABLE vocals (songid VARCHAR)