Hi @ijcua,
Yes, that’s what you’re looking for. It looks like you have a data problem – an entry in the submission_files table with a uploader_user_id that does not refer to an existing entry in the users table. You can pinpoint cases like this using the following query:
SELECT sf.* FROM submission_files sf LEFT JOIN users u ON (sf.uploader_user_id = u.user_id) WHERE u.user_id IS NULL;
Correct the uploader_user_id column for these entries and it should resolve the problem.
Regards,
Alec Smecher
Public Knowledge Project Team