System development/course/data items, attributes and relations

Relations
Draw together with the student some examples on a whiteboard or piece of paper. Explain what questions you should ask yourself to make the right decision about how a relation should be build in Triggre.

Possible examples are: * Employee – Person
 * Order – Orderrule
 * Start with a one to many relation.
 * Employee – Project
 * Then explain the many to many relation.
 * Person – LastName
 * In a lot of applications the relation between Person and LastName will be a 1-1 relation, LastName is an attribute of Person.
 * In SAP the lastname is registered in infotype 0002, see http://nl.sap.wikia.com/wiki/IT0002 for screenshot. At the top of the screen you can register a start an end date. Now the relation is a 1 to many relation.
 * Person – Address
 * In a lot of applications the relation between Peson and Address will be a 1-1 relation.
 * In an eHRM portal however you want to give your employees the opportunity to register their future move to a new house in advance. So you need a many to many relation.
 * Also add the concepts: Applicant, Contact.
 * Leasecare – driver