Room 5 of 10
Change the level of detail
Our question
How much detail does the waiting question need?
Back at Harbor Coffee
A conceptual model names the main ideas: people, orders, products, and handoffs. A domain or logical view adds rules and details such as Order Items, quantities, and readiness. An instantiated view shows Maria’s particular order.
The views describe the same situation at different levels. An accepted time can begin as an Order attribute. A single handoff time may later become inadequate: repeated Handoffs need their own times, contents, and participants. Detail earns its place when it helps answer a question.
Try a modeling decision
Choose a view to inspect. Each has a purpose.
Choose a view to see what it makes visible.
On the whiteboard
- Purpose → How much detail does the waiting question need?
Read the worked explanation
A direct Order–Product relationship is reasonable for discussing contents. Order Items can make quantities and per-item readiness explicit. Neither representation is universally better. Preserve identity and meaning as you zoom.
Room not yet explored. Capstone progress is separate.
Inspect the source
Order #9821
Supplied recordsupportedOn September 15 at 10:15, Maria ordered a latte and a muffin.
Contents of one purchase. No waiting-time measurement was supplied.
Name the concept
Conceptual model: A purpose-driven representation of the important concepts and connections. A domain/logical view adds rules and detail; an instantiated view shows particular examples.
Attribute / property: A descriptive fact attached to something, such as an order’s accepted time. It can become a separate thing when identity or history needs to be represented.
Instance: One particular thing, such as Maria or Order #9821.