I created Object Maps for my Smashing Events Project. The Object Map shows a list of Entities that would be used throughout the site, the Fields that each Entity would include and how the Entities link together. You can see this below:
From this, you can see my Event Content Type. You can see all the fields that are included in the Event Content type with the blue label. You can also see my Venue/Location Taxonomy Term, which also has Fields that are categorised by Blue. At the bottom of each list, you can see an item, labelled red. This indicates how the Event has a relationship with the Venue/Location and Vice Versa.
To show this in more detail, I installed a Drupal module that displays various Entities used around the site. As on the Trello Board above, I showed you the Event content type and Venue/Location Taxonomy term, I displayed the two entities in the Entity Relationship Diagram below:
You can see all the Fields that are included in the Event content type, including: Title, Event Date and Venue Location. You will also see, there’s an arrow coming from the venue_location field to the venue_location taxonomy term. This shows the relationship between the two, as an event, uses a venue/location Taxonomy term.