When employees at ABC Corp need to order supplies, they enter item data on a purchase requisition form (which is sent to supply requisition). A requisition clerk assigns a requisition number and stores the form in the requisition file.
Before the requisition can be stored, a supervisor must review the requisition and enter a code, to approve it. The requisition file is updated to reflect this approval.
Each day, a buyer in ABC's purchasing department accesses each approved requisition from the requisition file and verifies the requisition approver code against the authorised approver code list. If the code is valid, the buyer then accesses a list of approved vendors.
The buyer calls the selected vendor to establish item prices. Then the buyer adds the vendor number, the item prices agreed upon and the purchase order number to the requisition form and uses it to create a purchase order. Finally, the requisition file is updated, a copy of the purchase order is stored in the purchase order file, and the purchase order is mailed to the vendor.
Questions
1, Create a Physical context-level DFD for the supply requisition function for ABC corporation.
2, Create a level-0 diagram.
3, Create a level-1 diagram to describe more fully the functions associated with the buyer.
4, Ensure your set of DFDs are balanced.
5, Assume "Supervisor" is part of supply requisition function.
6, Draw these diagrams using Visio Pro.