SQL> show parameter undo
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
undo_management string AUTO --UNDO的管理方式:AUTO
undo_retention integer 900 --undo数据在undo段中保留的最大时间为900s
undo_tablespace string UNDOTBS1 --当前数据库默认的undo表空间
SQL> select name from v$datafile; (查看数据文件位置)
NAME
--------------------------------------------------------------------------------
/u01/app/oracle/oradata/sztech1/system01.dbf
/u01/app/oracle/oradata/sztech1/sysaux01.dbf
/u01/app/oracle/oradata/sztech1/undotbs01.dbf
/u01/app/oracle/oradata/sztech1/users01.dbf
/u01/app/oracle/oradata/sztech1/example01.dbf
SQL> alter system set undo_tablespace=undotbs2 scope=both;
System altered.
SQL> show parameter undo
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
undo_management string AUTO
undo_retention integer 900
undo_tablespace string UNDOTBS2