最近在做一個銀行的資料庫遷移及升級的case,由於該系統為統計跑批，原系統配置已經無法滿足跑批效能要求，故要購買新的主機採用ssd及hd兩種混合型的儲存，中間過程型的表對應的表空間放入ssd對應目錄，歷史結果表放入hd對應目錄。所以需要在遷移過程中對資料檔案進行移動和重新命名。以下是從網上搜索到的一篇文章，比較細緻的做了測試！記錄以下

同時此次，從oracle 11.2.0.4 遷移到12.2.0.01上，重點採用了oracle  12c的In_memory特性。對跑批效能提升有很大的幫助！特此記錄一下

下面介紹移動Oracle資料檔案的兩種方法。

1.alter database方法

該方法，可以移動任何表空間的資料檔案。

***關閉資料庫***
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.

***移動資料檔案，用oracle使用者操作***
[[email protected] ~]$ mv /u01/app/oracle/oradata/test/system01.dbf /oracledb/test/system01.dbf
[[email protected] ~]$ mv /u01/app/oracle/oradata/test/sysaux01.dbf /oracledb/test/sysaux01.dbf
[
 
[email protected] ~]$ mv /u01/app/oracle/oradata/test/undotbs01.dbf /oracledb/test/undotbs01.dbf
[[email protected] ~]$ mv /u01/app/oracle/oradata/test/users01.dbf /oracledb/test/users01.dbf
[[email protected] ~]$ mv /u01/app/oracle/oradata/test/temp01.dbf /oracledb/test/temp01.dbf
[[email protected] ~]$ mv /u01/app/oracle/oradata/test/redo03.log /oracledb/test/redo03.log
[
 
[email protected] ~]$ mv /u01/app/oracle/oradata/test/redo02.log /oracledb/test/redo02.log
[[email protected] ~]$ mv /u01/app/oracle/oradata/test/redo01.log /oracledb/test/redo01.log

***啟動到mount狀態***
SQL> startup mount
ORACLE instance started.

Total System Global Area 1.0122E+10 bytes
Fixed Size                  2237088 bytes
Variable Size            1610616160 bytes
Database Buffers         8489271296 bytes
Redo Buffers               19468288 bytes
Database mounted.

SQL> alter database rename file '/u01/app/oracle/oradata/test/system01.dbf' to '/oracledb/test/system01.dbf';

Database altered.

SQL> alter database rename file '/u01/app/oracle/oradata/test/sysaux01.dbf' to '/oracledb/test/sysaux01.dbf';

Database altered.

SQL> alter database rename file '/u01/app/oracle/oradata/test/undotbs01.dbf' to '/oracledb/test/undotbs01.dbf';

Database altered.

SQL> alter database rename file '/u01/app/oracle/oradata/test/users01.dbf' to '/oracledb/test/users01.dbf';

Database altered.

SQL> alter database rename file '/u01/app/oracle/oradata/test/temp01.dbf' to '/oracledb/test/temp01.dbf';

Database altered.

SQL> alter database rename file '/u01/app/oracle/oradata/test/redo01.log' to '/oracledb/test/redo01.log';

Database altered.

SQL> alter database rename file '/u01/app/oracle/oradata/test/redo02.log' to '/oracledb/test/redo02.log';

Database altered.

SQL> alter database rename file '/u01/app/oracle/oradata/test/redo03.log' to '/oracledb/test/redo03.log';

Database altered.

SQL> alter database open;

Database altered.

***重啟驗證***
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.

SQL> startup
ORACLE instance started.

Total System Global Area 1.0122E+10 bytes
Fixed Size                  2237088 bytes
Variable Size            1610616160 bytes
Database Buffers         8489271296 bytes
Redo Buffers               19468288 bytes
Database mounted.
Database opened.

2.alter tablespace方法

該方法，不能移動system表空間，回滾段表空間和臨時段表空間的資料檔案。

***offline system表空間時報錯***
SQL> alter tablespace system offline;
alter tablespace system offline
*
ERROR at line 1:
ORA-01541: system tablespace cannot be brought offline; shut down if necessary
報錯：說明system表空間不能offline
***由此說明一下system表空間的特性--不能離線offline
                              --不能置為只讀read only
                              --不能重新命名
                              --不能刪除

SQL> alter tablespace sysaux offline;

Tablespace altered.

[[email protected] ~]$ cp /oracledb/test/sysaux01.dbf /u01/app/oracle/oradata/test/sysaux01.dbf

SQL> alter tablespace sysaux rename datafile '/oracledb/test/sysaux01.dbf' to '/u01/app/oracle/oradata/test/sysaux01.dbf';

Tablespace altered.

SQL>  alter tablespace sysaux online;

Tablespace altered.

***offline UNDO表空間時報錯***
SQL> alter tablespace UNDOTBS1 offline;
alter tablespace UNDOTBS1 offline
*
ERROR at line 1:
ORA-30042: Cannot offline the undo tablespace

***offline TEMP表空間時報錯***
SQL> alter tablespace TEMP offline;
alter tablespace TEMP offline
*
ERROR at line 1:
ORA-03217: invalid option for alter of TEMPORARY TABLESPACE

#把需要移動的資料檔案對應的表空間offline
SQL> alter tablespace USERS offline;

Tablespace altered.

#移動資料檔案至目標位置
[[email protected] ~]$ cp /oracledb/test/users01.dbf /u01/app/oracle/oradata/test/users01.dbf

#修改表空間中資料檔案的位置
SQL> alter tablespace USERS rename datafile '/oracledb/test/users01.dbf' to '/u01/app/oracle/oradata/test/users01.dbf';

Tablespace altered.

#把表空間online
SQL> alter tablespace users online;

Tablespace altered.

3.總結

• alter database方法可以移動任何表空間的資料檔案，但其要求資料庫必須處於mount狀態，故此種方法更適合做整體資料庫的遷移。
• alter tablespace方法需要資料庫處於open狀態，表空間在offline的狀態下才可更改。但其不能移動system表空間，undo表空間和temp表空間的資料檔案，故此種方法更適合於做使用者資料檔案的遷移。