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When we look at the image above we see tables with titles and listed items, lines between these boxes connecting some of them and various figures on these connecting lines. The boxes represent the entities, building blocks of the organization schema. Looking at their names we can see that every one of them represents a meaningful real-world concept like Users, OrganizationUnits, Positions etc. Lists inside them contain their defined data fields. The line drawn between two entities shows that they have a relation. The name written on a line specifies the relation name and the arrow heads indicates the relation's direction(s). There are also different figures on the both ends of relation lines, which state the type of relation. See the image below for relation types:
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We can use a relation to go from one entity to another to get its associated data by using $Membership methods. For example assume that we want to get the department name of a workitem's initiator user. We can acquire it as in the example below:
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