ORA-16139: media recovery required错误处理

一、问题说明

在做物理DG主备库切换时，遇到ORA-16139: media recovery required错误

在当前备库执行过程展示如下：

SQL> select name,DATABASE_ROLE from v$database;NAME      DATABASE_ROLE
--------- ----------------
RUIADG    PHYSICAL STANDBYSQL> select name,DATABASE_ROLE from v$database;NAME      DATABASE_ROLE
--------- ----------------
RUIADG    PHYSICAL STANDBYSQL> select switchover_status from v$database;SWITCHOVER_STATUS
--------------------
SWITCHOVER LATENTSQL> alter database commit to switchover to primary;
alter database commit to switchover to primary
*
ERROR at line 1:
ORA-16139: media recovery required

二、原因定位

怀疑可能是由于有日志未应用造成的，执行如下语句查询：

SQL>  select APPLIED,SEQUENCE# from v$archived_log;APPLIED    SEQUENCE#
--------- ----------
YES                9
YES               10
YES               10
YES               11
YES               11
YES               12
YES               12
YES               13
YES               13
NO                14
YES               14APPLIED    SEQUENCE#
--------- ----------
NO                20
NO                17
NO                16
NO                15
NO                18
NO                19
NO                21
NO                22
NO                23
NO                24
NO                25APPLIED    SEQUENCE#
--------- ----------
NO                26
NO                27
NO                28
NO                2926 rows selected.

果然有很多日志未应用。

三、处理方式

执行如下命令：

SQL> ALTER  DATABASE RECOVER MANAGED STANDBY  DATABASE DISCONNECT FROM SESSION;Database altered.

再次执行切换命令：

SQL> alter database commit to switchover to primary;Database altered.

没有报错

此时查看数据库当前角色，已修改为Primary：

SQL> select name,DATABASE_ROLE from v$database;NAME      DATABASE_ROLE
--------- ----------------
RUIADG    PRIMARY