Left outer join
eSymphony's marketing department has noticed that songs in playlists get purchased more often. Since there's a Led Zeppelin anniversary coming up, they want to know how many songs composed by Jimmy Page, the founder of the band, are not in a playlist yet.
You decide to use a left outer join to solve this problem. By doing this, you are sure all tracks, even the ones that aren't included in a playlist, are shown.
Este exercício faz parte do curso
Introduction to Oracle SQL
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
SELECT t.TrackId, t.Composer, t.Name, p.PlaylistId
-- Perform a left outer join
FROM ___ ___ ___ ___ JOIN ___ p
-- Match on track id
ON ___.___ = ___.___