Hi @gaofzhan,   For what reason are you copying the JDBC driver to the NiFi's lib folder? When you need to JDBC driver for connecting to the remote sources, you typically only need to copy the ojdbc8.jar file. If you copy all the files that come in the tarball downloaded from Oracle it can cause errors like the one you describe.   Please remove the copied files from the lib folder, copy only the ojdbc8.jar one and try again.   Cheers, André -- Was your question answered? Please take some time to click on "Accept as Solution" below this post. If you find a reply useful, say thanks by clicking on the thumbs up button. ... View more