How to find the db size

Question

Hi ,
Please tell me how to find the db size.
Thanks,
Kumar.

Answer 1

If I understand correctly, the above query will give the space allocated to the database. This isn't necessarily the same as the space used by the database. Or do I need to clean my glasses ?
I use the following to get sizes for tablespaces (may need some formatting done - works in 9i and 10g) :
SELECT
     Total.name "TABLESPACE_NAME",
     total_space "TABLESPACE_SIZE",
     nvl(Free_space, 0) Free_space,
     nvl(total_space-Free_space, 0) Used_space
FROM
     select
          tablespace_name,
          sum(bytes/1024/1024) Free_Space
     from
          sys.dba_free_space
     group by
          tablespace_name
     ) Free,
     select
          b.name,
          sum(bytes/1024/1024) TOTAL_SPACE
     from
          sys.v_$datafile a,
          sys.v_$tablespace B
     where
          a.ts# = b.ts#
     group by
          b.name
     ) Total
WHERE
     Free.Tablespace_name(+) = Total.name
ORDER BY
     Total.name
;