Oracle DBA Script : Free Space left in the tablespaces

col tablespace_name format a20 heading 'Tablespace'

col allocated format 99,999,999,999 heading 'Allocated'

col used format 99,999,999,999 heading 'Used'

col unused format 99,999,999,999 heading 'Unused'

col pct_used format 99.99 heading 'PCT Used'

spool tbsp_free.lst

select rtrim(a.tblsp) tablespace,

sum(to_use) allocated,

sum(to_use - nvl(free,0)) used,

sum(nvl(free,0)) unused,

sum(((to_use-(to_use - nvl(free,0)))*100)/to_use) pct_used

from tspace_alc a,

tspace_free b

where a.tblsp = b.tblsp (+)

group by a.tblsp;