1. First download the instantclient_11_2 tool (http://download.csdn.net/detail/u013804636/9746431)
2. Add and configure the file tnsnames.ora under the directory instantclient_11_2\NETWORK\ADMIN\ in the downloaded tool
3. Add the following variables to the windows environment variables
TNS_ADMIN：E:\instantclient_11_2\NETWORK\ADMIN
NLS_LANG : SIMPLIFIED CHINESE_CHINA.AL32UTF8 (modified according to the encoding of the database, 16GBK)
4. Download and install plsql tool
5. Open plsql and select Tools->Oracle->Connect;
Modify the Oracle home directory to: E:\instantclient_11_2
The OCI library is: E:\instantclient_11_2\oci.dll
6. Apply, save, and restart the plsql client