dbms_metadata.get_ddl ORA-31603 ORA-06512

SQL> select * from v$version;

BANNER
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Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
PL/SQL Release 11.2.0.1.0 - Production
CORE 11.2.0.1.0 Production
TNS for 32-bit Windows: Version 11.2.0.1.0 - Production
NLSRTL Version 11.2.0.1.0 - Production

SQL> show user;
USER 为 "SCOTT"

SQL> SELECT dbms_metadata.get_ddl('TABLESPACE','USERS') FROM dual;
ERROR:
ORA-31603: 对象 "USERS" 属于类型 TABLESPACE, 在方案 "SCOTT" 中未找到
ORA-06512: 在 "SYS.DBMS_SYS_ERROR", line 105
ORA-06512: 在 "SYS.DBMS_METADATA", line 3912
ORA-06512: 在 "SYS.DBMS_METADATA", line 5678
ORA-06512: 在 line 1
未选定行

SQL> conn / as sysdba
已连接。
SQL> grant dba to scott;

授权成功。

SQL> conn scott/tiger
已连接。
SQL> set long 10000;

SQL> SELECT dbms_metadata.get_ddl('TABLESPACE','USERS') FROM dual;

DBMS_METADATA.GET_DDL('TABLESPACE','USERS')
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CREATE TABLESPACE "USERS" DATAFILE
'D:/ORACLE/LIANGWEI/ORADATA/LW/USERS01.DBF' SIZE 5242880
AUTOEXTEND ON NEXT 1310720 MAXSIZE 32767M
LOGGING ONLINE PERMANENT BLOCKSIZE 8192
EXTENT MANAGEMENT LOCAL AUTOALLOCATE DEFAULT NOCOMPRESS SEGMENT SPACE MANAGEM
ENT AUTO

SQL> SELECT DBMS_METADATA.GET_DDL('TABLESPACE', TS.TABLESPACE_NAME) CREATE_TBS_SQL
2 FROM USER_TABLESPACES TS
3 WHERE TS.TABLESPACE_NAME = 'USERS';

CREATE_TBS_SQL
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CREATE TABLESPACE "USERS" DATAFILE
'D:/ORACLE/LIANGWEI/ORADATA/LW/USERS01.DBF' SIZE 5242880
AUTOEXTEND ON NEXT 1310720 MAXSIZE 32767M
LOGGING ONLINE PERMANENT BLOCKSIZE 8192
EXTENT MANAGEMENT LOCAL AUTOALLOCATE DEFAULT NOCOMPRESS SEGMENT SPACE MANAGEM
ENT AUTO