DFD Examples

DFD Notation Data Flow : labeled arrow Sources and sinks of information/data (also called external entity) or Process or Available data (data store) or

Example: Air line reservation

DFD Example 1: Payroll

DFD Example 2: Old Car Mart Buys and sells old cars; has large number in stock: different models, make, year,colors,… Does some repairs for adding value; records kept; has own garage Advertise in news papers Salesmen hired on commission basis to handle customers, negotiate, etc. Needs to take stocks; prepare summary of sales, profits, etc; pay salesmen Prepare DFD

Example 3: Book Supplier Supplies books to customers; no stocks maintained; books sourced directly from publishers Prepare context diagrams

Book Supplier: Exploding Process 2