Capacity planing for oracle database

Database Growth Month wise:-

set pagesize 5000

tti "Database growth per month for last year"

select to_char(creation_time, 'RRRR Month') "Month",

       sum(bytes)/1024/1024 "Growth in Meg"

  from sys.v_$datafile

 where creation_time > SYSDATE-365

 group by to_char(creation_time, 'RRRR Month')

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