System Tablespace shows 99.8% used in Enterprise Manager

Information:  (question at the bottom)-
Oracle 10g R2 (10.2.0.3) Standard Edition
Windows 2003 SP2

The system datafile is set to auto extend and the system tablespace has Extent Management set to Local and Segment Space management set to manual.  Enterprise manager shows % used as 99.8 and Free (MB) as 1.1  
I did run the free.sql as found on AskTom.oracle.com and the results are:

Tablespace      KBytes      Used      Free      Used      Largest      MaxKbytes      MaxPctUsed
SYSTEM      501,760      500,672      1,088      99.8      960      33,554,416      1.5

This result would indicate that only 1.5 percent of the max allowed for this tablespace is used and that the datafile will extend until it reaches its max.  However, this query and the askTom thread made no mention of the Segment Space Management setting.

I also ran the following query to determine if the System table space is autoextensible:
select tablespace_name, autoextensible
from dba_data_files
group by tablespace_name, autoextensible;

The result for the SYSTEM tablespace is YES

I ran the following queries to determine if user objects are in the SYSTEM tablespace
select segment_name,segment_type
from dba_segments
where tablespace_name = 'SYSTEM';

and

select username, default_tablespace , temporary_tablespace
from dba_users
where default_tablespace = 'SYSTEM' or temporary_tablespace = 'SYSTEM';

The results of both indicate that there are no User objects in the System tablespace.
Questions:
My main question is, do I need to be concerned that this tablespace will not autoextend?  Will the System tablespace autoextend or will I get an Unable to extend type Oracle error?   If I have to create a second system datafile to increase the size of the system tablespace, can I create one while the DB is online and Do I need to make any changes to the existing datafile, like turn off autoextend?

I appreciate any help or direction given

Thanks-

SuzanneStart Free Trial