आप अपनी क्वेरी को इस रूप में बदल सकते हैं,
आपकी प्लेलिस्ट के गानों को छोड़कर डेटाबेस के सभी गानों के लिए
$sql1 = "Select distinct title, artist, album
from songs where id not in(Select distinct song.id
from songs song inner join playlist playlist
on playlist.song_id=song.id
inner join playlists playlists
on playlists.playlist_id=playlist.playlist_id
and playlists.name = '$playlist_name')";
जो आपकी प्लेलिस्ट में हैं,
$sql2 = "Select distinct song.title, song.artist, song.album
from songs song inner join playlist playlist
on playlist.song_id=song.id
inner join playlists playlists
on playlists.playlist_id=playlist.playlist_id
and playlists.name = '$playlist_name'";