how many dorms have a TV Lounge?
select count(*) from dorm as t1 join has_amenity as t2 on t1.dormid = t2.dormid join dorm_amenity as t3 on t2.amenid = t3.amenid where t3.amenity_name = 'TV Lounge'
what are their names?
select t1.dorm_name from dorm as t1 join has_amenity as t2 on t1.dormid = t2.dormid join dorm_amenity as t3 on t2.amenid = t3.amenid where t3.amenity_name = 'TV Lounge'
what are the names of dorms that do not have it?
select dorm_name from dorm except select t1.dorm_name from dorm as t1 join has_amenity as t2 on t1.dormid = t2.dormid join dorm_amenity as t3 on t2.amenid = t3.amenid where t3.amenity_name = 'TV Lounge'