SELECT albumid, COUNT(trackid) FROM tracks GROUP BY albumid;
SELECT albumid, COUNT(trackid) FROM tracks GROUP BY albumid ORDER BY COUNT(trackid) DESC;
SELECT tracks.albumid, title, COUNT(trackid) FROM tracks INNER JOIN albums ON albums.albumid = tracks.albumid GROUP BY tracks.albumid;
SELECT tracks.albumid, title, COUNT(trackid) FROM tracks INNER JOIN albums ON albums.albumid = tracks.albumid GROUP BY tracks.albumid HAVING COUNT(trackid) > 15;
SELECT albumid, sum(milliseconds) length, sum(bytes) size FROM tracks GROUP BY albumid;
SELECT tracks.albumid, title, min(milliseconds), max(milliseconds), round(avg(milliseconds),2) FROM tracks INNER JOIN albums ON albums.albumid = tracks.albumid GROUP BY tracks.albumid;
SELECT mediatypeid, genreid, count(trackid) FROM tracks GROUP BY mediatypeid, genreid;
SELECT * FROM albums;
SELECT * FROM artists;
SELECT * FROM customers;
SELECT * FROM employees;
SELECT * FROM genres;
SELECT * FROM invoice_items;
SELECT * FROM invoices;
SELECT * FROM media_types;
SELECT * FROM playlist_track;
SELECT * FROM playlists;
SELECT * FROM tracks;