查看并設置oracle數據的歸檔模式

1.改變非歸檔模式到歸檔模式:
1)以DBA身份連接數據庫，查看是否為歸檔模式
SQL> conn / as sysdba
SQL> archive log list;
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 31
Current log sequence 33
2)立即關閉數據庫
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
3)啟動實例并加載數據庫到mount狀態
SQL> startup mount
ORACLE instance started.
Total System Global Area 1224736768 bytes
Fixed Size 2020384 bytes
Variable Size 318770144 bytes
Database Buffers 889192448 bytes
Redo Buffers 14753792 bytes
Database mounted.
4)更改數據庫為歸檔模式
SQL> alter database archivelog;
Database altered.
5)打開數據庫
SQL> alter database open;
SQL> SELECT NAME,created,log_mode FROM v$database;
NAME CREATED LOG_MODE

      ORCL      04-JUN-12 ARCHIVELOG
      Database altered.
 6)啟用自動歸檔   10G之前需要操作
      SQL> alter system archive log start;
 8）查看歸檔日志的路徑和目錄
      SQL> show parameter db_recovery_file_dest;
      NAME TYPE VALUE
      ------------------------------------ ----------- ------------------------------
      db_recovery_file_dest string /data/app/oracle/flash_recovery_area
      db_recovery_file_dest_size big integer 2G
 9）修改方法歸檔日志位置及大小：
      SQL> alter system set db_recovery_file_dest_size=20g;
      SQL> alter system set db_recovery_file_dest='/app/arc';