cx_Oracle was renamed to python-oracledb in the May 2022 release. It now comes with two modes, thin and thick. Thick mode uses the Oracle client libraries to connect to Oracle, while thin mode can connect directly. cx_Oracle previously always required using the Oracle client libraries.
Is there any performance implications to using the thin mode instead of the thick mode?
Yes, there is, but it can vary depending on your workload. In our own tests we saw basic fetching and inserting performing with thin mode between 10% and 30% faster than thick mode. The main reason for the difference is the elimination of a copy/conversion step that is required in thick mode. Some more discussion can be found here: https://github.com/oracle/python-oracledb/discussions/5.
