The scenario
A library management system where patrons borrow books. This Level 1 DFD shows the main process 'Borrow Book' interacting with the Patron external entity and the Book Inventory data store.
What is in this drawing
Read the decisions behind it.
01
No conditional branches; continuous data flows between entities, process, and store.
When modeling the top-level data flows of a library borrowing system; can be extended for more detailed processes.
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