Which artists have released volumes?
select distinct artist from artist where artist_id in(select artist_id from volume)
Whose volumes lasted more than 2 weeks on top?
select distinct t1.artist from artist as t1 join volume as t2 on t1.artist_id = t2.artist_id where t2.weeks_on_top > 2
Whose volumes also lasted less than 2 weeks on top?
select t1.artist from artist as t1 join volume as t2 on t1.artist_id = t2.artist_id where t2.weeks_on_top > 2 intersect select t1.artist from artist as t1 join volume as t2 on t1.artist_id = t2.artist_id where t2.weeks_on_top < 2
What are their famous titles?
select t1.famous_title from artist as t1 join volume as t2 on t1.artist_id = t2.artist_id where t2.weeks_on_top > 2 intersect select t1.famous_title from artist as t1 join volume as t2 on t1.artist_id = t2.artist_id where t2.weeks_on_top < 2