update floor set fk_building = 3 where fk_building != 3 and floor_id = 1;

select * from floor where fk_building != 3

update floor set fk_building = 3 where (not fk_building <=> 3) and floor_id = 1;

update floor set fk_building = 3 where (fk_building != 3 OR fk_building IS NULL) and floor_id = 1;