A relation item in a model describes the relationships between entities.
This section describes the steps to add a relation between the Orders and Customers entities such that many Orders records corresponds to zero or one Customers record.
To add a new relation, click the Add Entity button on top of the model editor.
In the Add Relationship dialog box that appears, enter the name for the new relation.
Set the relationship cardinality to a required field from the drop-down such as 'N to 0..1'. Apart from this, you can specify whether to enable a bidirectional cross filter and make the relation inactive through the Bidirectional Cross Filter and Make Relation Inactive properties.
In the Relations section, set the target entity by selecting it from the drop-down list. Then add the required source column and a target column that appear below.
Click the Add button. A newly added relation will appear in the list of relations of the data model's entity.