See the Instant Client Home Page for more information about Instant Client.
The installation instructions are at the foot of the page.Version 19.3
1. Download the appropriate Instant Client packages for your platform. All installations REQUIRE the Basic package.
2. Unzip the packages into a single directory such as "instantclient".
3. Set the library loading path in your environment to the directory in Step 2 ("instantclient"). On AIX, LIBPATH is the appropriate environment variable.
4. Start your application and enjoy.