Chapter Summary

Chapter 13

Specifying Data Requirement

© Karl E. Wiegers

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1. Entity-Relationship Diagram

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3 Partial entity-relationship diagram for the Chemical Tracking System

-Relationship -Cardinality

2. Class Diagram (used in UML) - see also chapter 12

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Class Diagram for ATM

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3. Data Dictionary (used in data Flow Diagram)

Uses BNF (extended) notation This has 3 fundamental constructs.

sequence  selection    Repetition { }

( ) optional = is compose of

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 Ex. name  name =title + First-name + (middle-name)

+ last-name  title =[Mr | Miss | Mrs…]  First-name = {legal-char}1

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 Middle-name = {legal-char}1 10 at least

 Last-name = {legal-char}1 12

 Legal-char = [A-Z  a-z -]

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4. Data Analysis CRUD Matrix gives relationship between

Use-cases and data objects (see below)

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 CRUD can show possibly missing requirement

- There is no “D” for an object “requester” - What does it mean? - Possibly a missing requirement ?

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END

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