When adding an SQL database as a datasource, the following error message might be printed when testing the connection:

Cannot connect to this database. Error message was:
[JDBC driver class not found: oracle.jdbc.driver.OracleDriver]
CODE

This means that the appropriate JDBC driver, which is needed to connect to the database, is missing. You need to download it manually and add it to the folder WEB-INF/lib of your Confluence installation directory. After that restart Confluence. You can find a list of the JDBC drivers here. 

For a detailed step-by-step tutorial, refer to our Getting Started Guide.