检查日志文件是否传输到备用数据库

例如：我配置归档位置如下： 

SQL> show parameter log_archive_dest_2

NAME                                 TYPE                              VALUE
------------------------------------ --------------------------------- ------------------------------
log_archive_dest_2                   string                            SERVICE=dg2 LGWR ASYNC
                                                                          VALID_FOR=(ONLINE_LOGFILES,
                                                                       PRIMARY_ROLE)
                                                                          DB_UNIQUE_NAME=DGTest2

可以查询v$archive_dest视图来查看归档位置是否归档，statu列如果为valid，说明归档成功，可以查看error列得到不能归档的原因

SQL> select dest_name,status,error from v$archive_dest where dest_id=2;

DEST_NAME            STATUS     ERROR
-------------------- ---------- --------------------
LOG_ARCHIVE_DEST_2   VALID