text: Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
  ### Context:
  CREATE TABLE songs (title VARCHAR, songid VARCHAR); CREATE TABLE vocals (songid VARCHAR)
  ### Question:
  Find all the songs that do not have a back vocal.
  ### Answer:
  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"