Download 64 Oracle installation;
download PL / SQL installation;
download instantclient-basic-win32-12.1.0.1.0.zip, cut instantclient_12_1 folder after extracting paste to the Oracle product installation directory folder;
from Oracle Installation under the NETWORK copy the folder G: \ oracle11g \ app \ Administrator \ product \ 11.2.0 \ dbhome_1), and paste it into instantclient_12_1 folder;
without logging in open PL / SQL, in tools - Preferences - connection (tool> preferences > connection)
modify Oracle home directory name (e.g., G: \ oracle11g \ app \ Administrator \ product \ instantclient_12_1)
modified OCI libraries (e.g., G: \ Oracle11g \ App \ Administrator \ Product \ instantclient_12_1 \ the oci.dll)
6. The closed PL / SQL, re-open, log it, the connection is successful! ! !
Remember, maybe path is selected at instantclient_12_1 folder, not in the oracle installation folder, and if the wrong file path will pop up the following error:
