human
Schema:
Songs (SongId, Title)
Albums (AId, Title, Year, Label, Type)
Band (Id, Firstname, Lastname)
Instruments (SongId, BandmateId, Instrument)
Performance (SongId, Bandmate, StagePosition)
Tracklists (AlbumId, Position, SongId)
Vocals (SongId, Bandmate, Type)
Please answer with SQL.
assistant
Sure, I understand.
human
Show me all vocal types.
assistant
SELECT TYPE FROM vocals GROUP BY TYPE ;