define m_tablespace = 'TEST_8K' 
    
select 
    file_id,  
    block_id,  
    block_id + blocks - 1   end_block,  
    owner,  
    segment_name,  
    partition_name,  
    segment_type  
from 
    dba_extents  
where 
    tablespace_name = '&m_tablespace' 
union all 
select 
    file_id,  
    block_id,  
    block_id + blocks - 1   end_block,  
    'free'          owner,  
    'free'          segment_name,  
    null            partition_name,  
    null            segment_type  
from 
    dba_free_space  
where 
    tablespace_name = '&m_tablespace' 
order by 
    1,2  
/ 