Oracle Database Discussions

hi gurus

i have some confusion regarding database size.

as i query select sum(bytes/1024/1024) "mb" from dba_data_files its giving a constant value 107480

but the values of dba_free_space and dba_segments is different.I want to know how much my database size is increaing everyday(means i need to maintain a record of my database size increaing each day).So please through some light by acknowleging below queries.

as on day1

SQL> select sum(bytes/1024/1024) "mb" from dba_data_files;

mb
----------
107480

SQL> SELECT SUM(bytes)/1024/1024 "Meg" FROM dba_segments;

Meg
----------
82096.625

SQL> SELECT SUM(bytes)/1024/1024 "Meg" FROM dba_free_space;

Meg
----------
26572.875

as on day 2

SQL> select sum(bytes/1024/1024) "mb" from dba_data_files;

mb
----------
107480

SQL> SELECT SUM(bytes)/1024/1024 "Meg" FROM dba_segments;

Meg
----------
82344

SQL> SELECT SUM(bytes)/1024/1024 "Meg" FROM dba_free_space;

Meg
----------
26325.5

so is the database increased size is the value of dba_segments from day2-day1 or dba_data_files-dba_free_space.

is it 82344-82096=248

so 248kb