Tempfile not re-created during recovery

Question

Hello,
While running an RMAN recovery of a 10g instance, I noticed in the alert log the fact that the tempfile belonging to the TEMP tablespace is not re-created.
My instance is recovered using a backup controlfile, and all datafiles (except the tempfile) are re-created.
Normally, during the dictionary check I'm getting the error messages (ORA-01157, 01110, 27037) that report the missing file temp01.dbf, and the file is created.
However, during this particular recovery, the dictionary check was completed without any errors reported in the alert log, then the following message appears:
WARNING: The following temporary tablespaces contain no files.
This condition can occur when a backup controlfile has
been restored. It may be necessary to add files to these
tablespaces. That can be done using the SQL statement:
ALTER TABLESPACE <tablespace_name> ADD TEMPFILE
Alternatively, if these temporary tablespaces are no longer
needed, then they can be dropped.
Empty temporary tablespace: TEMP
The message contains the solution to fix the problem, but I would like to know why it appeared in the first place.
Thank you for any ideas,
Adrian

Answer 1

that mean add tempfile... on temp tablespace:
SQL> ALTER TABLESPACE temp ADD TEMPFILE '/oradata/temp02.dbf' SIZE 512m AUTOEXTEND ON NEXT 250m MAXSIZE UNLIMITED;
Or add new default temp tablespace:
SQL> CREATE TEMPORARY TABLESPACE temp2 TEMPFILE '/oradata/temp02.dbf' SIZE 5M REUSE AUTOEXTEND ON NEXT 1M MAXSIZE unlimited EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M;
SQL> ALTER DATABASE DEFAULT TEMPORARY TABLESPACE temp2;
SQL> DROP TABLESPACE temp INCLUDING CONTENTS AND DATAFILES;
SQL> CREATE TEMPORARY TABLESPACE temp TEMPFILE '/oradata/temp01.dbf' SIZE 500M REUSE AUTOEXTEND ON NEXT 100M MAXSIZE unlimited EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M;
SQL>ALTER DATABASE DEFAULT TEMPORARY TABLESPACE temp;
SQL> DROP TABLESPACE temp2 INCLUDING CONTENTS AND DATAFILES;
http://www.idevelopment.info/data/Oracle/DBA_tips/Tablespaces/TBS_3.shtml