Find the solution:
1.show parameter undo
2.create UNDO tablespace UNDO2 datafile '/u01/app/oracle/oradata/ora10g/undotbs02.dbf' size 200M REUSE AUTOEXTEND ON NEXT 10M MAXSIZE 500M;
1.show parameter undo
2.create UNDO tablespace UNDO2 datafile '/u01/app/oracle/oradata/ora10g/undotbs02.dbf' size 200M REUSE AUTOEXTEND ON NEXT 10M MAXSIZE 500M;
3.alter system set undo_tablespace = 'UNDO2'后再用第一步查看
4.drop tablespace undotbs1 including contents cascade constraints;
5.use os cmd 'rm 'authentic undotbs01.dbf file;