Schedule weekly database / tablespace growth report

Hi All,

I'm looking for ways to scheduled a weekly job to gather database or tablespace growth report.

Currently I'm using a very basic query and scheduled it via cron to retrieve the database size every week.

Is there any better query which I can use? My databases do not have any diagnostic pack licenses.

col "Database Size" format a20

col "Free space" format a20

col "Used space" format a20

select round(sum(used.bytes) / 1024 / 1024 / 1024 ) || ' GB' "Database Size"

, round(sum(used.bytes) / 1024 / 1024 / 1024 ) -

round(free.p / 1024 / 1024 / 1024) || ' GB' "Used space"

, round(free.p / 1024 / 1024 / 1024) || ' GB' "Free space"

from (select bytes