Instance Mappings vs Mapping Rules

In the Studio a data mapping essentially consists of a collection of instance mappings. Structurally each instance mapping has a target entity and a single source expression. The source expression is used to determine which source instances must be mapped to instances of the target entity. When starting with an empty target profile, each source instance will result in the creation of one new instance of the target entity. Additionally it is also possible to define additional context expressions, which can be used to activate an additional source instance when determining attribute and relation values.

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For example a given source profile has 5 instances of type Person, which must be mapped to 5 instances of type Customer in a given empty target profile. There are in total 5 source instances, but they will each be mapped independently from each other to a Customer instance. In this case we consider the mapping rule to have 1 source instance and 1 target instance. 

Direct

The Direct rule type is most simple rule type. It is used in scenarios where a single instance in the source profile must be mapped to a single instance in the target profile.

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The following table defines how we determine to which rule type an instance mapping will be transformed from the Studio to the Model Mapper.