You must add the Instant Client directory to the system PATH environment variable. This must be performed before attempting to run any application.
You can choose the Basic package for full functionality or the Basic Lite package (smaller footprint) if you only need English error messages and standard character sets like Unicode. Why Stick with 19c in 2026? oracle instant client 19c
FROM python:3.9-slim
It eliminates the need for complex registry settings or a traditional ORACLE_HOME environment variable for basic connectivity. You must add the Instant Client directory to
Instant Client 19c is the standard for containerized environments. Because it is "stateless" regarding installation, it is perfect for Docker images. it is perfect for Docker images.