在搭建好的11.2.0.3的ADG(Active DataGuard)中，standby端的alert日志中
总是不定期出现同一个sql id的sql语句报ora-1555的错误，经确认，发现是bug，简单做下记录。
Affects:
Product (Component) Oracle Server (Rdbms) Range of versions believed to be affected (Not specified) Versions confirmed as being affected Platforms affected Generic (all / most platforms affected)
Fixed:
Description
The fix for 13814252 is first included in
This bug is only relevant when using RAC (Real Application Clusters) / OPS and Active Dataguard (ADG)Spurious ORA-1555 errors may be seen in RAC Active Dataguard
解决方法
文档中并没有给出workaround的方法，既然在11.2.0.4或者更高的版本已经修复了该bug。也就是可以升级到11.2.0.4 来解决
这个问题。因为这个ora-1555是spurious（虚假的），这里我选择了忽略该错误。
参考
Bug 13814252 - Spurious ORA-1555 in RAC Active Dataguard (文档 ID 13814252.8)