While working on my Windows x64 test server, trying to reproduce (yet another) critical Oracle bug related to compressed tables, I thought some help from the GUI tool can easy my research. Of course, my first thought was to use SQL Developer, but in this particular case Toad was a better choice. Since all other Oracle Software installed on this test box is 64-bit, I didn’t want to install full blown 32-bit Oracle client just for the sake of running Toad. Instead I downloaded 32-bit Oracle instant client 11.1.0.6.

My first attempt of setting environment was something like this:

:: Oracle11g (32-bit, instant client)
title Oracle11 (32-bit, instant client)
set PATH=D:\ORACLE\instantclient_11_1;%PATH%
set ORACLE_HOME=D:\ORACLE\instantclient_11_1
set TNS_ADMIN=D:\ORACLE\instantclient_11_1
start D:\ORACLE\Toad\Toad

The important part is line with SET PATH, where I put 11g client in the front of other directories, already in the path variable, including some 10g homes. It happens that this is not enough. It’s mandatory that you exclude from the path all other Oracle client software that is not part of the instant client.

So the version that works is slightly modified:

:: Oracle11g (32-bit, instant client)
title Oracle11 (32-bit, instant client)
set PATH=D:\ORACLE\instantclient_11_1;%WINDIR%;%WINDIR%\SYSTEM32
set oracle_home=D:\ORACLE\instantclient_11_1
set TNS_ADMIN=D:\ORACLE\instantclient_11_1
start D:\ORACLE\Toad\Toad

When you run Toad for the first time you’ll likely see combo box with empty list of TNS aliases. Don’t worry, just key in Oracle TNS alias that you want to connect to (assuming that you put valid TNSNAMES.ORA, SQLNET.ORA in the directory from TNS_ADMIN variable).

Disclaimer:
Installing client GUI tools, such as Toad on production server(s) is not recommended – don’t do it :-). I chose to install Toad on this particular test server because the machine is in the sand-box environment that prevents connectivity from the net.