set lines 200
col datafile for a60
col file_name for a50
SELECT dfs.tablespace_name tablespace,
       ddf.file_name datafile,
       dfs.bytes / 1024 / 1024 free_mb,
       dfs.block_id start_block,
       (dfs.block_id + dfs.blocks) - 1 end_block, 
       ddf.blocks last_files_block
  from dba_free_space dfs, dba_data_files ddf
 where dfs.tablespace_name = upper('&tablespace')
   and dfs.file_id = ddf.file_id
 order by ddf.file_name, dfs.block_id;

/*-- --*/  
 select 
	TABLE_NAME, 
	ROUND((AVG_ROW_LEN * NUM_ROWS / 1024), 2) SIZE_KB 
from 
	dba_TABLES 
where 
	TABLE_NAME = 'LF_DETREL';