What are the names of all games that were played for at least 1000 hours?
select gname from plays_games as t1 join video_games as t2 on t1.gameid = t2.gameid group by t1.gameid having sum ( hours_played ) > = 1000
What are the names of all games that were played for less than 1000 hours?
select gname from plays_games as t1 join video_games as t2 on t1.gameid = t2.gameid group by t1.gameid having sum ( hours_played ) < 1000
What are the average hours played for each game type?
select t2.gtype, avg ( t1.hours_played ) from plays_games as t1 join video_games as t2 on t1.gameid = t2.gameid group by t2.gtype