开启归档模式及其相关参数(三)
_dest_state_ 参数为系统维护提供方便，
归档日志物理路径状态被设置为DEFER时，ORACLE不会对这路径进行归档操作。
可以在某一归档日志目录出错时使用此参数，正常后再修改，可以不影响数据库系统的正常运行。
如以后路径状态改为ENABLE，所丢失的归档文件必须手工恢复。
SQL> show parameterlog_archive_dest_state_
NAME TYPE VALUE
----------------------------------------------- ------------------------------
log_archive_dest_state_1 string enable
SQL> select destination,binding,target,status from v$archive_dest;
DESTINATION BINDING TARGET STATUS
------------------------------ ---------------- ---------
d:\disk1\offlinelog\ MANDATORY PRIMARY VALID
d:\disk2\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk3\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk4\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk5\offlinelog\ MANDATORY PRIMARY VALID
OPTIONAL PRIMARY INACTIVE
SQL> alter system set log_archive_dest_state_1 = defer;
系统已更改。
SQL> select destination,binding,target,status from v$archive_dest;
DESTINATION BINDING TARGET STATUS
------------------------------ ---------------- ---------
d:\disk1\offlinelog\ MANDATORY PRIMARY DEFERRED
d:\disk2\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk3\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk4\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk5\offlinelog\ MANDATORY PRIMARY VALID
OPTIONAL PRIMARY INACTIVE
SQL>
alter system set log_archive_dest_state_1 = enable;
系统已更改。
SQL> show parameter log_archive_dest_state_1
NAME TYPE VALUE
----------------------------------------------- ------------------------------
log_archive_dest_state_1 string ENABLE
SQL> select destination,binding,target,status from v$archive_dest;
DESTINATION BINDING TARGET STATUS
------------------------------ ---------------- ---------
d:\disk1\offlinelog\ MANDATORY PRIMARY VALID
d:\disk2\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk3\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk4\offlinelog\ OPTIONAL PRIMARY VALID
d:\disk5\offlinelog\ MANDATORY PRIMARY VALID
OPTIONAL PRIMARY INACTIVE