oracle重建undo表空间

create undo tablespace UNDOTBS2 datafile 'D:\oracle\product\10.2.0\oradata\ttonline\UNDOTBS02.DBF' size 500m reuse autoextend on next 100m;
alter system set undo_tablespace=UNDOTBS2 scope=both;
drop tablespace UNDOTBS1 INCLUDING CONTENTS AND DATAFILES CASCADE CONSTRAINTS;

shutdown immediate;

startup mount;

alter database open;