今天打开数据库，想修改oracle的归档模式结果出现以下错误：
- SQL> alter database archivelog;
- alter database archivelog
- *
- ERROR at line 1:
- ORA-00265: instance recovery required, cannot set ARCHIVELOG mode
上网查了下，原来是上次系统的非正常关闭导致。需要重新打开数据库，使数据文件，控制文件，日志文件同步，再修改归档模式。
- SQL> alter database open;
- Database altered.
- SQL> shutdown immediate;
- Database closed.
- Database dismounted.
- ORACLE instance shut down.
- SQL> startup mount;
- ORACLE instance started.
- Total System Global Area 301305856 bytes
- Fixed Size 1336148 bytes
- Variable Size 167775404 bytes
- Database Buffers 125829120 bytes
- Redo Buffers 6365184 bytes
- Database mounted.
- SQL> alter database archivelog;
- Database altered.
- SQL> alter database open;
- Database altered.
重新查看数据库归档模式：
- SQL> archive log list
- Database log mode Archive Mode
- Automatic archival Enabled
- Archive destination USE_DB_RECOVERY_FILE_DEST
- Oldest online log sequence 6
- Next log sequence to archive 8
- Current log sequence 8
OK！
