plsql 登录后提示：
Database character set (AL32UTF8) and Client character set (ZHS16GBK) are different.
Character set conversion may cause unexpected results.
Note: you can set the client character set through the NLS_LANG environment variable or the NLS_LANG registry key in
HKEY_LOCAL_MACHINE\SOFTWARE\Oracle\KEY_OraClient11g_home2.
解决办法：修改注册表
打开注册表,‘开始’-‘运行’ 输入‘regedit’-确定。
找到提示中给出的路径，
(在win10 64位系统中，按照提示并不能找到路径，网上百度了下,64位系统和32位系统不一样，最终的答案是)
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Oracle\KEY_OraClient11g_home2.
找到 NLS_LANG 键，他的值原来是：SIMPLIFIED CHINESE_CHINA.ZHS16GBK
修改为：SIMPLIFIED CHINESE_CHINA.AL32UTF8
重新打开plsql ，登录，好了。