bbPress.org

Diana, maybe this link helps you. https://wpengine.com/support/run-query-phpmyadmin/

In bbpress, topics and replies are kept in wp_posts table, so the above SQL statement lists all users with no replies and no topics. The second part of the statement checks the wp_comments table. Since if a user has no replies & topics in the forum but has a wordpress comment, the user will not be listed, and vice versa.

Please first also check your table prefix, the SQL statement is for: wp_

If you still have problems, you can contact me via move2media.com