Sometimes it can be very useful to have the option to assign attributes of one object to another object, e.g. if some data is not consistent or simply if an attribute is missing and exists within another object. This operation can be accomplished by configuring object assignment layers in the project configuration.

 

 

 

The following configuration shall be described with an easy example. Granted that there exist two layers, one layer representing properties and another cadaster layer where several attributes of the properties are saved. Now the attribute parcel number of the cadaster layer should be assigned to the properties layer.

 

In order to enable object assignment the following steps have to be performed:

 

•Configure an edit layer which will serve as the target layer of the object assignment. Thus, there needs to exist at least the Edit field where the assigned attribute will be written into. In the next step the minimum required edit actions are Assign and Edit. Finally it is necessary to define an object assignment layer which points to the source layer of the attribute to be assigned.
With the example above, the properties layer is the target layer to be edited. The attribute of the parcel number' will be written into the edit field KG_GNR. The cadaster layer will be used as the object assignment layer since it is the origin of the attribute parcel number.

 

 

•In the next step it is necessary to define layer queries for at least two layers with one layer providing the attribute to be assigned and the other one serving as target layer for the assignment. Therefore, the attribute to be assigned needs to be configured as search field in the source layer. A list of predefined queries or a full text search can be useful if objects to be assigned are far away from each other in the map. Additionally, an object assignment needs to be configured within the source layer defining its primary key field and the foreign key field of the target layer. Using object assignment the primary key field gets read and stored to the foreign key field of the defined edit layer. Finally, another layer query has to be configured for the target layer including search and result fields at least for the editable field.
The parcel number attribute KG_GNR of the cadaster layer will be configured as search and result field together with a predefined query. Additionally, the node object assignment defines the parcel number KG_GNR as primary key field. The parcel number field KG_GNR of the target properties layer will serve as foreign key field. Finally the target properties layer must be at least identifiable.