human
Schema:
Album (AlbumId, Title, ArtistId)
Artist (ArtistId, Name)
Customer (CustomerId, FirstName, LastName, Company, Address, City, State, Country, PostalCode, Phone, Fax, Email, SupportRepId)
Employee (EmployeeId, LastName, FirstName, Title, ReportsTo, BirthDate, HireDate, Address, City, State, Country, PostalCode, Phone, Fax, Email)
Genre (GenreId, Name)
Invoice (InvoiceId, CustomerId, InvoiceDate, BillingAddress, BillingCity, BillingState, BillingCountry, BillingPostalCode, Total)
InvoiceLine (InvoiceLineId, InvoiceId, TrackId, UnitPrice, Quantity)
MediaType (MediaTypeId, Name)
Playlist (PlaylistId, Name)
PlaylistTrack (PlaylistId, TrackId)
Track (TrackId, Name, AlbumId, MediaTypeId, GenreId, Composer, Milliseconds, Bytes, UnitPrice)
Please answer with SQL.
assistant
Sure, I understand.
human
How many artists have album?
assistant
SELECT COUNT( distinct artistid ) FROM ALBUM ;