SQL> Col type_ heading "File type"
SQL> Col kb format 99G999G999G990 heading "Size (Kb)"
SQL> Break on report
SQL> Compute sum label "Total" of kb on report
SQL> Prompt
SQL> Select 'Datafiles' type_, round(sum(bytes/1024)) kb from dba_data_files
2 union all
3 Select 'Tempfiles' type_, round(sum(bytes/1024)) kb from dba_temp_files
4 union all
5 Select 'Redologs' type_, round(sum(bytes*members)/1024) kb from v$log
6 /
File type Size (Kb)
--------- ---------------
Datafiles 1,986,560
Tempfiles 276,480
Redologs 81,920
---------------
Total 2,344,960
Regards
Michel