Tablespaces that are >=80% full, and how much to add to make them 80% again

set pages 999 lines 100
col "Tablespace" for a20
col "Size MB"  for 999999999
col "%Used"  for 999
col "Add (80%)"  for 999999999
select tsu.tablespace_name "Tablespace",
       ceil(tsu.used_mb) "Size MB",
       100 - floor(tsf.free_mb / tsu.used_mb * 100) "%Used",
       ceil((tsu.used_mb - tsf.free_mb) / .8) - tsu.used_mb "Add (80%)"
  from (select tablespace_name, sum(bytes) / 1024 / 1024 used_mb
          from dba_data_files
         group by tablespace_name) tsu,
       (select ts.tablespace_name, nvl(sum(bytes) / 1024 / 1024, 0) free_mb
          from dba_tablespaces ts, dba_free_space fs
         where ts.tablespace_name = fs.tablespace_name(+)
         group by ts.tablespace_name) tsf
 where tsu.tablespace_name = tsf.tablespace_name(+)
   and 100 - floor(tsf.free_mb / tsu.used_mb * 100) >= 80
 order by 3, 4
/

Результат:

Tablespace             Size MB %Us Add (80%)
-------------------- --------- --- ---------
SYSAUX                     657  95  122,9375
SYSTEM                     700 100       169

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