Example Student Apprenticeship - Adding Constraints
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Example Student Apprenticeship
City of Residence
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Adding Constraints
Transform to relational
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Adding Constraints

After the initial qualification of expressions we've now build up the repository, but there's not a single constraint declared yet. In the diagram we can now select the roles and place different types of constraints.

Unique constraints

  • Student: 'Firstname, Lastname'
  • City: 'City name'
  • Apprenticeship Preference: 'Student, Number'
  • Apprenticeship Preference: 'Student, Apprenticeship'
  • Apprenticeship: 'Apprenticeship Code'
  • etc...

Totality constraints

  • Student: 'City of Residence'
  • Apprenticeship: 'Apprenticeship City'
  • Apprenticeship: 'Apprenticeship Description'
  • City (This constraint means that the population of city must be filled with occurrences from 'City of Residence' and/or 'Apprenticeship City' and nothing else.)

Value Constraints

  • Number: '1, 2, 3'

After placing all the constraints the previously created diagram will be automatically updated with this new information.


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