best.sql

SELECT creation.subject_id
FROM   creation
       JOIN item
         ON creation.object_id = item.id

SELECT item.creation_subject_id
FROM   item

SELECT customer.display_name
FROM   customer
       JOIN creation
         ON customer.id = creation_subject_id
       JOIN item
         ON creation.object_id = item.id

SELECT customer.display_name
FROM   customer
       JOIN item
         ON customer.id = item.creation_subject_id

SELECT item.creation_subject_user_display_name
FROM   item