1. You'll want to register an additional Database Service: https://github.com/OpenRefine/OpenRefine/blob/master/extensions/database/src/com/google/refine/extension/database/DatabaseService.java
2. Provide the connection and service classes, look at the PostgreSQL one or MySQL one as examples: https://github.com/OpenRefine/OpenRefine/tree/master/extensions/database/src/com/google/refine/extension/database
3. Then wire up the interface with defaults as desired: https://github.com/OpenRefine/OpenRefine/blob/master/extensions/database/module/scripts/index/database-source-ui.js#L93
4. Add drivers manually to the classpath, or update the pom file to provide them as dependencies as other DB libraries are done: https://github.com/OpenRefine/OpenRefine/blob/master/extensions/database/pom.xml
