Database Free space report

Tablespace Name: name of tablespace, leading '*' indicates a good locally managed tablespace, leading blank means it is a bad dictionary managed tablespace. Second character of A implies ASSM managed storage, second character of M implies manually managed (pctused, freelists, etc are used to control space utilization)
Kbytes: allocated space of the tablespace, sum of kbytes consumed by all datafiles associated with tablespace.
Used: space in the tablespace that is used by some segment.
Free: space in the tablespace not allocated to any segment.
%Used: ratio of free to allocated space
largest: mostly useful with dictionary managed tablespaces, the size of the largest contigously set of blocks available. If this number in a dictionary managed tablespace is smaller than the next extent for some object, that object could fail with "out of space" even if the FREE column says there is lots of free space.
MaxPoss Kbytes: the autoextend max size (note CAN be smaller than the allocated size!!!! you can set the maxsize to be less than the current size of a file)
%Max Used: how much of the maximum autoextend size has been used so far


set linesize 121
-------------------------------------------------------
-- free.sql  
--
-- This SQL Plus script lists freespace by tablespace
--------------------------------------------------------

column dummy noprint
column  pct_used format 999.9       heading "%|Used" 
column  name    format a19      heading "Tablespace Name" 
column  Kbytes   format 999,999,999    heading "KBytes" 
column  used    format 999,999,999   heading "Used" 
column  free    format 999,999,999  heading "Free" 
column  largest    format 999,999,999  heading "Largest" 
column  max_size format 999,999,999 heading "MaxPoss|Kbytes"
column  pct_max_used format 999.9       heading "%|Max|Used" 
break   on report 
compute sum of kbytes on report 
compute sum of free on report 
compute sum of used on report 

select (select decode(extent_management,'LOCAL','*',' ') || 
               decode(segment_space_management,'AUTO','a ','m ')
	      from dba_tablespaces where tablespace_name = b.tablespace_name) || nvl(b.tablespace_name, 
			 nvl(a.tablespace_name,'UNKOWN')) name,
	   kbytes_alloc kbytes, 
	   kbytes_alloc-nvl(kbytes_free,0) used,
	   nvl(kbytes_free,0) free, 
	   ((kbytes_alloc-nvl(kbytes_free,0))/ 
						  kbytes_alloc)*100 pct_used,
	   nvl(largest,0) largest,
	   nvl(kbytes_max,kbytes_alloc) Max_Size,
	   decode( kbytes_max, 0, 0, (kbytes_alloc/kbytes_max)*100) pct_max_used
from ( select sum(bytes)/1024 Kbytes_free, 
			  max(bytes)/1024 largest,
			  tablespace_name
	   from  sys.dba_free_space 
	   group by tablespace_name ) a,
     ( select sum(bytes)/1024 Kbytes_alloc, 
			  sum(maxbytes)/1024 Kbytes_max,
			  tablespace_name 
	   from sys.dba_data_files 
	   group by tablespace_name 
	   union all
      select sum(bytes)/1024 Kbytes_alloc, 
			  sum(maxbytes)/1024 Kbytes_max,
			  tablespace_name 
	   from sys.dba_temp_files 
	   group by tablespace_name )b
where a.tablespace_name (+) = b.tablespace_name
order by &1
/

If you are stuck on software written last century:


--------------------------------------------------------
-- free.sql
--
-- This SQL Plus script lists freespace by tablespace
--------------------------------------------------------
                                                                                                         
column dummy noprint
column  pct_used format 999.9       heading "%|Used"
column  name    format a19      heading "Tablespace Name"
column  Kbytes   format 999,999,999    heading "KBytes"
column  used    format 999,999,999   heading "Used"
column  free    format 999,999,999  heading "Free"
column  largest    format 999,999,999  heading "Largest"
column  max_size format 999,999,999 heading "MaxPoss|Kbytes"
column  pct_max_used format 999.9       heading "%|Max|Used"
break   on report
compute sum of kbytes on report
compute sum of free on report
compute sum of used on report
                                                                                                         
select (select decode(extent_management,'LOCAL','*',' ')
          from dba_tablespaces where tablespace_name = b.tablespace_name) ||
nvl(b.tablespace_name,
             nvl(a.tablespace_name,'UNKOWN')) name,
       kbytes_alloc kbytes,
       kbytes_alloc-nvl(kbytes_free,0) used,
       nvl(kbytes_free,0) free,
       ((kbytes_alloc-nvl(kbytes_free,0))/
                          kbytes_alloc)*100 pct_used,
       nvl(largest,0) largest,
       nvl(kbytes_max,kbytes_alloc) Max_Size,
       decode( kbytes_max, 0, 0, (kbytes_alloc/kbytes_max)*100) pct_max_used
from ( select sum(bytes)/1024 Kbytes_free,
              max(bytes)/1024 largest,
              tablespace_name
       from  sys.dba_free_space
       group by tablespace_name ) a,
     ( select sum(bytes)/1024 Kbytes_alloc,
              sum(maxbytes)/1024 Kbytes_max,
              tablespace_name
       from sys.dba_data_files
       group by tablespace_name
       union all
      select sum(bytes)/1024 Kbytes_alloc,
              sum(maxbytes)/1024 Kbytes_max,
              tablespace_name
       from sys.dba_temp_files
       group by tablespace_name )b
where a.tablespace_name (+) = b.tablespace_name
order by &1
/

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