File mismatch

Question

I had a linux 10g with 10g xe installed.
I stopped db, removed all db files and xe stuff, and installed 11g xe.
Then I created 2 extra tablespaces and imp(orted) a datafile with 10.2.0.3.0 oracle user's tables (from node 1 of a clustered enterprise edition database).
Here is what I get, very strange:
select ts.name, da.name, da.bytes, ta.status
from dba_tablespaces ta, v$tablespace ts,
v$datafile da
where da.ts#=ts.ts#
and ts.name=ta.TABLESPACE_NAME;
NAME
NAME
BYTES STATUS
SYSTEM
/u01/app/oracle/oradata/XE/system.dbf
377487360 ONLINE
SYSAUX
/u01/app/oracle/oradata/XE/undotbs1.dbf
555745280 ONLINE
UNDOTBS1
*/u01/app/oracle/oradata/XE/sysaux.dbf
5620367360 ONLINE*
USERS
/u01/app/oracle/oradata/XE/users.dbf
5242880 ONLINE
UNDOTBS2
/u01/app/oracle/oradata/XE/XE/datafile/o1_mf_undotbs2_6zyjnnxw_.dbf
104857600 ONLINE
INDX
/u01/app/oracle/oradata/XE/XE/datafile/o1_mf_indx_70oxvj27_.dbf
1048576000 ONLINE
T_JOBINS
/u01/app/oracle/oradata/XE/XE/datafile/o1_mf_t_jobins_6zyjqlbw_.dbf
10485760 ONLINE
USR
/u01/app/oracle/oradata/XE/XE/datafile/o1_mf_usr_6zykwso9_.dbf
104857600 ONLINE
ABIEC
/u01/app/oracle/oradata/XE/XE/datafile/o1_mf_abiec_70oxw6rw_.dbf
2097152000 ONLINE
9 rows selected.
SQL>
Problem 1:
undotbs1 is undo tablespace of 10.2.0.3.0 db.
Sysaux tablespace now works with undotbs1.dbf datafile, and undotbs1 undo tablespace now uses sysaux.dbf.
why why why? (This would have been difficult to do this using sql :) ).
Problem 2: sysaux.dbf datafile size grew to 5 Gb, I will have to look how to shrink it.

Answer 1

Tablespace-datafile names mix up reported earlier in {thread:id=2207251}.