Atlassian ends support for the data source connections for external data sources in Confluence 8.0. It recommends switching to a direct JDBC connection from the existing JNDI data source connections. For more information, refer to Configuring a data source connection.
Considering Confluence 8.x upliftment, the SQL for Confluence app will no longer support the JNDI data source connections. The already configured data source based profiles will have to be converted to connection string profiles. Our team is working on this and will soon release the SQL for Confluence app update and the related documentation.