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Datastore Descriptions for the Current Physical Dataflow Model (slide 21)

The Datastore Descriptions for Current Physical Dataflow Model for the Feasibility Study of Acme Fashion case study, s21
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Datastore Descriptions

In the current physical, datastores come in many shapes and sizes:

  • In / Out trays
  • Filing cabinets
  • Desk stick pins
  • 'Rolodex'-style files
  • Catalogues and other forms of reference material (e.g. DVD)
  • Computer-based databases

Remember, a datastore is some holding point where data comes to rest. Use either Cs or Ms for clerical / manual datastores (your choice) and Ds for computer / automated ones.

The datastores listed in the table below all come from the top level DFD. Others are used that are private to the processes shown on it and will be documented when those processes are decomposed. For example, Sales Operations uses a mini database (their 'master sales spreadsheet) to record orders and print off the dispatch and delivery notes.

Ref Name Description Containing LDM Entities
C1 Customer Master File A filling cabinet used to store all paper records to do with the customer.
The contents shown are not complete as it is also used by out-of-scope areas (e.g. Accounts) for other purposes.
Customer, Sales Order, Sales Order Line, Returns, Returns Line
C2 Stock Master File A set of A6 stock record cards held in filling trays in the stock room. It is key to keeping control over the stock and is used both by the stock room staff and Goods Inwards. Size, Style, Colour, Product, Product Sources, Supplier, Purchase Order, Purchase Order Line

To be completed.

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