① ASM文件转化
以创建的asmtest表空间为例
㈠ 将os文件转换为ASM文件
sys@ORCL> create tablespace asmtest datafile size 10m;
Tablespace created.
sys@ORCL> alter tablespace asmtest offline;
Tablespace altered.
[oracle@localhost ~]$ rman target /
RMAN> backup as copy tablespace asmtest format '+DATA';
RMAN> switch tablespace asmtest to copy;
datafile 6 switched to datafile copy "+DATA/orcl/datafile/asmtest.256.798497595"
sys@ORCL> alter tablespace asmtest online;
Tablespace altered.
sys@ORCL> select file_name from dba_data_files where tablespace_name='ASMTEST';
FILE_NAME
----------------------------------------------------------------------------------------------------
+DATA/orcl/datafile/asmtest.256.798497595
ASMCMD> mkalias ASMTEST.256.798497595 asmtest.dbf
ASMCMD> ls -al
Type Redund Striped Time Sys Name
DATAFILE MIRROR COARSE NOV 04 20:00:00 Y +DATA/ORCL/DATAFILE/asmtest.dbf => ASMTEST.256.798497595
N asmtest.dbf => +DATA/ORCL/DATAFILE/ASMTEST.256.798497595
㈡ 将数据文件从一个diskgroup迁移到另一个diskgroup
idle> select file_id from dba_data_files where tablespace_name='ASMTEST';
FILE_ID
----------
6
idle> alter tablespace asmtest offline;
[oracle@localhost ~]$ rman target /
RMAN> backup as copy datafile 6 format '+THINK';
RMAN> switch datafile 6 to copy;
RMAN> recover datafile 6;
RMAN> sql "alter tablespace asmtest online";
ASMCMD> find THINK/ *
+THINK/ORCL/
+THINK/ORCL/DATAFILE/
+THINK/ORCL/DATAFILE/ASMTEST.256.798503425
㈢ 将ASM文件转发成OS文件
sys@ORCL> select file_name from dba_data_files where tablespace_name='ASMTEST';
FILE_NAME
----------------------------------------------------------------------------------------------------
+THINK/orcl/datafile/asmtest.256.798503425
sys@ORCL> alter tablespace asmtest offline;
sys@ORCL> create directory ossrc as '/home/oracle';
sys@ORCL> create directory asmsrc as '+THINK/orcl/datafile';
sys@ORCL> begin
2 dbms_file_transfer.copy_file('ASMSRC','ASMTEST.256.798503425','OSSRC','ASM.DBF');
3 end;
4 /
PL/SQL procedure successfully completed.
sys@ORCL> alter database rename file '+THINK/orcl/datafile/asmtest.256.798503425' to '/home/oracle/ASM.DBF';
[oracle@localhost ~]$ rman target /
RMAN> recover datafile 6;
RMAN> sql "alter tablespace asmtest online";
sys@ORCL> select file_name from dba_data_files where tablespace_name='ASMTEST';
FILE_NAME
----------------------------------------------------------------------------------------------------
/home/oracle/ASM.DBF
② ASM中的文件名
ASM文件名，诸如：
+THINK/orcl/datafile/asmtest.256.798503425
上述名称的生成格式为：
+diskgroup/dbname/file_type/file_type_tag.file.incarnation
● +diskgroup ：磁盘组名称
● dbname ：数据库的DB_UNIQUE_NAME参数值
● file_type ：创建的文件类型，比如CONTROLFILE/DATAFILE/ONLINELOG/ARCHIVELOG/TEMPFILE/BACKUPSET/FLASHBACK等等
● file_type_tag ：文件类型的标签，比如表空间对应的通常为该表空间名称
● file.incarnation ：文件序号+incarnation，用来确保文件的唯一
文件创建时无法指定实际文件名及路径，完全由ORACLE的OMF控制和管理
例如：
sys@ORCL> alter tablespace asmtest add datafile '+DATA' size 10m;
Tablespace altered.
如果设置了初始化参数db_create_file_dest，甚至连磁盘组名都不需要写了
其它类型文件，比如重做日志文件等，操作方式都是同理的
但像trace文件、alert文件、dump文件等还不能直接被存储到ASM中