Oracle 10g ORA-12154: TNS: could not resolve the connect identifier specified

我先装了oracle9,再安装了pl/sql dev，这时我输入用户名、口令可以连接服务器。

随后我再安装了ODAC 11.2 Release 4 (11.2.0.3.0) with Oracle Developer Tools for Visual Studio，我再使用pl/sql dev联接时，报错

Oracle 10g ORA-12154: TNS: could not resolve the connect identifier specified

查看Path系统环境变量时发现

E:\app\Administrator\product\11.2.0\client_1;E:\app\Administrator\product\11.2.0\client_1\bin;F:\oracle\ora90\bin;

client变量在前，更改成

F:\oracle\ora90\bin;E:\app\Administrator\product\11.2.0\client_1;E:\app\Administrator\product\11.2.0\client_1\bin;

就OK