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.