原因：

二、將掛載裝置卸下時出現的錯誤

# umount /usr/local/

umount: /usr/local: device is busy

解決方法：fuser –km /usr/local/

fuser的用法:

       -k     Kill processes accessing the file. Unless changed with -signal, SIGKILL is

              sent.  An  fuser process never kills itself, but may kill other fuser pro-

              cesses. The effective user ID of the process executing fuser is set to its

              real user ID before attempting to kill.

       -m     name specifies a file on a mounted file system or a block device  that  is

              mounted. All processes accessing files on that file system are listed.  If

              a directory file is specified, it is automatically changed  to  name/.  to

              use any file system that might be mounted on that directory.

三、資料庫安裝驗證過程中出現的錯誤

Checking Network Configuration requirements ...
Actual Result: :java.lang.NullPointerException:Exception/Error Occurred
Check complete. The overall result of this check is: Not executed <<<<
Recommendation: Oracle supports installations on systems with DHCP-assigned public IP

addresses.  However, the primary network interface on the system should be configured with a

static IP address in order for the Oracle Software to function properly.  See the

Installation Guide for more details on installing the software on systems configured with

DHCP.

解決方法：新增主機認證

[root@vaxph97 ~]# vi /etc/hosts

# Do not remove the following line, or various programs

# that require network functionality will fail.

127.0.0.1               localhost.localdomain localhost

::1             localhost6.localdomain6 localhost6

192.168.1.97 vaxph97

四、匯出指定資料物件（其中匯出過程中需要轉義）

其中單引號中的內容一定要用大寫（上面的圖片中寫成了小寫，因為不會排除這兩個檢視）

五、解決CENTOS上scp的安裝問題

錯誤程式碼：

-bash: scp: command not found

解決方法：

配置YUM

輸入yum install openssh-clients即可

六、解決expdp過程中ORA-28000和ORA-01017的錯誤

ora-28000錯誤為賬戶被鎖，需要解鎖賬戶（包括system賬戶）

解決方法：alter user system account unlock

ORA-01017為密碼過期或不可用，更改密碼即可

解決方案：alter user system identified by system

七、解決oracle庫使用者無法刪除問題

1.可以現在資料庫層面解決

解決方法

SQL> select username ,sid,serial# from v$session;

查出sid,serial#號

然後，透過資料庫命令kill掉sid和serial#

SQL> alter system kill session 'sid,serial#';

2.如果kill不掉，可以透過系統命令來進行查詢spid程式號

SQL> select p.username ,p.spid from v$session s ,v$process p where s.PADDR=p.addr and s.sid=147;

USERNAME             SPID

-------------------- ------------------------

oracle               18134

然後透過系統命令kill掉該程式

> kill -9 18134

3.如果仍然drop不掉使用者，則可以將監聽佔時關閉，防止使用者透過遠端連線連線資料庫

>lsnrctl stop