应该在操作系统模式下还是数据库模式下？

[alongjuan]

备份和恢复数据库中的对象应该在操作系统模式下还是数据库模式下？

操作系统是AIX，数据库是ORACLE8.1.7

[alongjuan]

其实我问题的实质是：是不是不用在连接数据库的情况下就可以用EXP/IMP

比如说我是不是要：Connect internal或者Connect其他的用户模式下才执行可以导入和导出。还是我直接在AIX的命令形式下就可以执行导入和导出操作，如果在AIX命令模式下就可以，那么他是根据什么依据去发现数据库中的对象而执行相应的操作？

我现在发现直接在AIX的命令下，键入：

[ibmb80:/]exp help=y
ksh: exp: not found.

而用：

[ibmb80:/]su - oracle
[ibmb80:oracle:/home/oracle]exp help=y

Export: Release 8.1.7.0.0 - Production on Thu Aug 21 15:18:45 2003

(c) Copyright 2000 Oracle Corporation. All rights reserved.



You can let Export prompt you for parameters by entering the EXP
command followed by your username/password:

Example: EXP SCOTT/TIGER

Or, you can control how Export runs by entering the EXP command followed
by various arguments. To specify parameters, you use keywords:

Format: EXP KEYWORD=value or KEYWORD=(value1,value2,...,valueN)
Example: EXP SCOTT/TIGER GRANTS=Y TABLES=(EMP,DEPT,MGR)
or TABLES=(T1:P1,T1:P2), if T1 is partitioned table

USERID must be the first parameter on the command line.

Keyword Description (Default) Keyword Description (Default)
--------------------------------------------------------------------------
USERID username/password FULL export entire file (N)
BUFFER size of data buffer OWNER list of owner usernames
FILE output files (EXPDAT.DMP) TABLES list of table names
COMPRESS import into one extent (Y) RECORDLENGTH length of IO record
GRANTS export grants (Y) INCTYPE incremental export type
INDEXES export indexes (Y) RECORD track incr. export (Y)
ROWS export data rows (Y) PARFILE parameter filename
CONSTRAINTS export constraints (Y) CONSISTENT cross-table consistency
LOG log file of screen output STATISTICS analyze objects (ESTIMATE)
DIRECT direct path (N) TRIGGERS export triggers (Y)
FEEDBACK display progress every x rows (0)
FILESIZE maximum size of each dump file
QUERY select clause used to export a subset of a table
VOLSIZE number of bytes to write to each tape volume

The following keywords only apply to transportable tablespaces
TRANSPORT_TABLESPACE export transportable tablespace metadata (N)
TABLESPACES list of tablespaces to transport

Export terminated successfully without warnings.

这说明导入和导出需要在一定的模式下才行。谁能具体告诉我这是为什么吗？

[kerisyml]

这个问题问的有点怪，你在AIX模式下直接用exp就可以执行备份。
用imp导入数据库