[Oracle] datafile重新ONLINE

當Oracle的部份datafile OFFLINE時,必須手動執行ONLINE,步驟如下
1.sqlplus sys/(密碼)@(SID) as sysdba (如 sqlplus sys/123456@x01 as sysdba)
2.select status from v$instance; (確認Oracle是否OPEN)
3.SELECT TABLESPACE_NAME FROM DBA_TABLESPACES WHERE STATUS = 'OFFLINE';
4.SELECT NAME FROM V$DATAFILE WHERE STATUS = 'RECOVER';
5.RECOVER DATAFILE 'G:\ORACLE\X01\SAPDATA1\UNDO_1\UNDO.DATA1';
6.ALTER DATABASE DATAFILE 'G:\ORACLE\X01\SAPDATA1\UNDO_1\UNDO.DATA1' 'ONLINE';