My data consists of a Point-shp (parent layer), a table (child layer), and a 1-N relation between these layers. The point layer represents trees. In this point-layer there is an attribute called
Plot_ID, indicating where the tree is located.
After creating a tree, several characteristics of the tree can be inserted (CREATING FEATURES IN CHILD LAYER), each characteristic created would be a feature in the table layer.
In the child layer there is also a specific column for indicating the
Plot_ID. Now, I'd like to copy the attribute value of the specific feature of the parent layer to the feature that is being created from the child layer. This is, if parent is called e.g. 'A', the features from the child from this parent 'A', will copy this
For aclaration, the process would consist as follows:
1) Create point
1.1) Fill atributes:
fid = 1
uniqueID = 2abc-3cde-4fgh
Plot_ID = P1
2) Create feature in child layer
2.1) Fill attributes:
fid = 1
fk_field = 2abc-3cde-4fgh
Plot_ID = P1 --> through an automatic expression
What I'm looking for is to automatically set an expression that gets the attribute value of the parent layer (
Plot_ID), when creating a feature in the child layer. Then, everytime I create a point, and then a child feature, it will automatically get the attribute value
Plot_ID from its parent feature.
What I've tried
I've already tried approaches like 1.,
relation_aggregate, and expressions like
attribute(@parent, 'Plot_ID'), but none of them gave me the result I was looking for. In the case of
relation_aggregate, the relation between my two layers was somehow not recognized and gave me no value as an output (found no solution about this in internet either).