col owner form a15 head 'Owner'
col table_name form a25 head 'Table'
col Sze form 999,999,999 head 'Size (MB)'
col Percentage form 990.09

break -
	on owner skip 1

prompt
prompt Row Chaining
prompt ============
prompt

select 	owner,
	table_name, 
	(blocks*8192)/(1024*1024) Sze, 
	num_rows, 
	chain_cnt, 
	(chain_cnt/num_rows)*100 as Percentage
From dba_tables 
where chain_cnt != 0
order by owner, 6 desc;