for thnee in #django IRC

query.py

# Given this doesn't work
qs = Song.objects
qs = qs.prefetch_related(
    db.models.Prefetch(
        "releases", queryset=SongRelease.objects.raw(
            """
            SELECT id, target FROM tungsten_song_release;
            """
        ),
    )

# why not do?
class PartialSongRelease(models.Model):
    id = models.WhateverField(primary_key=True)
    target = models.WhateverField(...)
    
    class Meta:
        managed = False
        db_table = "tungsten_song_release"
    
Song.objects.prefetch_related(Prefetch("releases", queryset=PartialSongRelease.objects.all()))