Do I need multiple DATA/INDX tablespaces for a DB on a SAN?

Question

Is there any advantage to creating multiple DATA and INDEX tablespaces for databases that are on a SAN? Database size is probably going to be around 1TB per year.
Our databases are normally smaller and perform well with a single DATA tablespace and single INDEX tablespace. I would like to see if we need to use a different approach with a larger db and a SAN in place.
Thanks

Answer 1

Justin
As a follow up to my previous post, yes I can confirm that extent allocation is round robin across all files in a TS. The test outline I gave mentioned rowid but as I reconstructed the test that turned out to be irrelevant.
Here is the results:
SQL> drop tablespace bubba_ts
2      INCLUDING CONTENTS AND DATAFILES;
Tablespace dropped.
SQL> create SMALLFILE tablespace bubba_ts
2      datafile 'c:\oradata\edst\bubbatbs_01.dbf'
3           size 1m
4           autoextend off,
5           'c:\oradata\edst\bubbatbs_02.dbf'
6           size 1m
7           autoextend off,
8           'c:\oradata\edst\bubbatbs_03.dbf'
9           size 1m
10           autoextend off
11      EXTENT MANAGEMENT LOCAL UNIFORM SIZE 64K;
Tablespace created.
SQL> drop user bubba;
User dropped.
SQL> create user bubba
2      identified by bubbapw
3      default tablespace bubba_ts
4      temporary tablespace temp
5      quota unlimited on bubba_ts;
User created.
SQL> grant create session,
2      create table
3 to bubba;
Grant succeeded.
SQL> create table bubba.rowid_test
2      (
3      key_col number,
4      big_col1 char(2000),
5      big_col2 char(2000),
6      big_col3 char(2000)
7      );
Table created.
SQL> BEGIN
2      for i in 1..100 loop
3      insert into bubba.rowid_test
4      values (i,
5           'xxxxx',
6           'xxxxx',
7           'xxxxx'
8           );
9      end loop;
10 END;
11 /
PL/SQL procedure successfully completed.
SQL> col file_name for a35
SQL> select e.extent_id,
2      e.file_id,
3      f.file_name
4 from dba_extents e,
5      dba_data_files f
6 where e.owner = 'BUBBA'
7 and e.segment_name = 'ROWID_TEST'
8 and e.file_id = f.file_id
9 order by e.extent_id
10 ;
EXTENT_ID FILE_ID FILE_NAME
0 10 C:\ORADATA\EDST\BUBBATBS_03.DBF
1 8 C:\ORADATA\EDST\BUBBATBS_01.DBF
2 9 C:\ORADATA\EDST\BUBBATBS_02.DBF
3 10 C:\ORADATA\EDST\BUBBATBS_03.DBF
4 8 C:\ORADATA\EDST\BUBBATBS_01.DBF
5 9 C:\ORADATA\EDST\BUBBATBS_02.DBF
6 10 C:\ORADATA\EDST\BUBBATBS_03.DBF
7 8 C:\ORADATA\EDST\BUBBATBS_01.DBF
8 9 C:\ORADATA\EDST\BUBBATBS_02.DBF
9 10 C:\ORADATA\EDST\BUBBATBS_03.DBF
10 8 C:\ORADATA\EDST\BUBBATBS_01.DBF
11 9 C:\ORADATA\EDST\BUBBATBS_02.DBF
12 10 C:\ORADATA\EDST\BUBBATBS_03.DBF
13 8 C:\ORADATA\EDST\BUBBATBS_01.DBF