Tablespace's health

Hello DBAs !

We are using Oracle 6.0.34, HP-UX 9.0.
We have just one small database and the default tablespace, system. Our database files looks like this:

-rw-r----- 1 oracle dba 28160 Jan 31 07:58 cntrloracle.dbf
-rw-r----- 1 oracle dba 10487808 Jan 31 11:08 dbsoracle.dbf
-rw-r--r-- 1 oracle dba 310 Feb 21 1992 init.ora
-rw-r--r-- 1 oracle dba 944 Feb 21 1992 initbig.ora
-rw-r--r-- 1 oracle dba 937 Feb 21 1992 initmed.ora
-rw-rw-r-- 1 oracle dba 309 Feb 19 1993 initoracle.ora
-rw-r----- 1 oracle dba 512512 Jan 30 17:49 log1oracle.dbf
-rw-r----- 1 oracle dba 512512 Jan 31 11:07 log2oracle.dbf
-rw-rw---- 1 oracle dba 372 Jan 31 07:57 sgadeforacle.dbf
-rw-r--r-- 1 oracle dba 28367 Feb 21 1992 sql.bsq

My question is, how can I determine if the system tablespace is big enough for our needs, and for how long ? Currently we have about 40 tables, with indexes, sequences etc., but I need in next days to add some new table and our data will double.

I know there is some query to see free space etc, but I really have some problem to evaluate this values...
Is someone of you so kind to give me some hints?

sys:SQL> select substr(OWNER,1,10) OWNER, substr(SEGMENT_NAME,1,15) SEGMENT,   2 HEADER_BLOCK, BYTES, BLOCKS, EXTENTS, MAX_EXTENTS from dba_segments   3 order by owner, SEGMENT_NAME;

OWNER SEGMENT HEADER_BLOCK BYTES BLOCKS EXTENTS MAX_EXTENTS
---------- --------------- ------------ ---------- ---------- ---------- -----------

PRO        T01                     2921      10240          5          1          99
PRO        T02                     2916      20480         10          2          99
PRO        T02IX                   2956      20480         10          2          99
PRO        T02IX2                  4201      22528         11          2          99
PRO        T03                     2896      10240          5          1          99

sys:SQL> select substr(owner,1,10) OWNER, substr(segment_name,1,25) NAME,   2 substr(SEGMENT_TYPE,1,10) TYPE, BLOCK_ID, BYTES, BLOCKS from sys.dba_extents   3 order by owner, segment_type, segment_name;

OWNER      NAME                      TYPE         BLOCK_ID      BYTES     BLOCKS


---------- ------------------------- ---------- ---------- ---------- ----------


PRO        T02IX                     INDEX            2956      10240          5
PRO        T02IX                     INDEX            3170      10240          5
PRO        T02IX2                    INDEX            4201      12288          6
PRO        T02IX2                    INDEX            4196      10240          5
PRO        T04IX                     INDEX            2961      14336          7

sys:SQL> select tablespace_name Tablespace_Name, sum(bytes) Free_Bytes,   2 max(bytes) Largest_Free_Extent, count(bytes) Nr_Of_Free_Extents   3 from dba_free_space group by tablespace_name;

TABLESPACE_NAME                FREE_BYTES LARGEST_FREE_EXTENT NR_OF_FREE_EXTENTS


------------------------------ ---------- ------------------- ------------------


SYSTEM                            1294336              423936                 21

Thank you!
Stefano
--

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