CREATE UNDO TABLESPACE UNDOTBS2 DATAFILE '/u01/app/oracle/oradata/XE/UNDOTBS2_1.dbf' SIZE 10485760;

ALTER SYSTEM SET UNDO_TABLESPACE=UNDOTBS2 SCOPE=BOTH;

-- kill all sessions

-- wait for value of undo_retention (default 900)

DROP TABLESPACE UNDOTBS1 INCLUDING CONTENTS AND DATAFILES;

CREATE UNDO TABLESPACE UNDOTBS1 DATAFILE '/u01/app/oracle/oradata/XE/UNDOTBS1.dbf' SIZE 10485760;

ALTER SYSTEM SET UNDO_TABLESPACE=UNDOTBS1 SCOPE=BOTH;

-- kill all sessions

-- wait for value of undo_retention (default 900)

DROP TABLESPACE UNDOTBS2 INCLUDING CONTENTS AND DATAFILES;