ORA-01093错误解决

环境是RAC+RAC的DG的10.2.0.5环境

当时是把主备库打开，想启动MRP进程（实时应用），但是执行语句时出现1093错误：SQL> alter database recover managed standby database ;
alter database recover managed standby database
*
ERROR at line 1:
ORA-01093: ALTER DATABASE CLOSE only permitted with no sessions connectedSQL> ！oerr ora 1093
01093, 00000, "ALTER DATABASE CLOSE only permitted with no sessions connected"
// *Cause: There is at least one more session other than the current one
// logged into the instance. ALTER DATABASE CLOSE is not permitted.
// *Action: Find the other sessions and log them out and resubmit the command上面说的很清楚：原因是多于一个的会话连接当前数据库实例。ALTER DATABASE CLOSE is not permitted;解决办法是退出该会话；

字面意思没有很懂，当我查看主备库状态时发现备库处于只读状态：

SQL> select open_mode from gv$database;
OPEN_MODE
----------
READ ONLY
READ ONLY哎，粗心误大事啊，启动实时应用备库需要在mount状态下的；解决办法是，把备库启动到mount状态下，再执行：SQL> shutdown immediate;
Database closed.
Database dismounted.
Oracle instance shut down.
SQL> startup mount;
ORACLE instance started.
Total System Global Area 327155712 bytes
Fixed Size 1273516 bytes
Variable Size 96469332 bytes
Database Buffers 226492416 bytes
Redo Buffers 2920448 bytes
Database mounted.
SQL> alter database recover managed standby database disconnect from session;Database altered.ok，问题解决，其实就是要注意启用MRP，备库要处于MOUNT状态下进行

（注意：Oracle 10g，要在mount状态下，才能开启MRP。然而11g在open就可以）Oracle 11g 在RedHat Linux 5.8_x64平台的安装手册 http://www.linuxidc.com/Linux/2014-07/104745.htmLinux-6-64下安装Oracle 12C笔记 http://www.linuxidc.com/Linux/2013-07/86805.htm在CentOS 6.4下安装Oracle 11gR2（x64） http://www.linuxidc.com/Linux/2014-02/97374.htmOracle 11gR2 在VMWare虚拟机中安装步骤 http://www.linuxidc.com/Linux/2013-09/89579p2.htmDebian 下安装 Oracle 11g XE R2 http://www.linuxidc.com/Linux/2014-03/98881.htm更多Oracle相关信息见Oracle 专题页面 http://www.linuxidc.com/topicnews.aspx？tid=12本文永久更新链接地址