Top Segments ordered by Physical Reads

col segment_name format a20

col owner format a10 

select segment_name,object_type,total_physical_reads

 from ( select owner||'.'||object_name as segment_name,object_type,

value as total_physical_reads

from v$segment_statistics

 where statistic_name in ('physical reads')

 order by total_physical_reads desc)

 where rownum < 10;