All Questions
39
questions
0
votes
0
answers
18
views
Relation QGIS: get_feature
I have 2 layers (1 polygon / 1 no-geometry (aType)). I have a relation between them.
As we know, we can display 1 value from the related layer via layer property -> Attributes Form.
In the widget ...
- 467
0
votes
1
answer
38
views
QGIS - Avoid duplicates on Value-Relation widget
In QGIS, I'm working with two layers that are related to each other through the value-relation widget.
Layer 1: TEST
fields: "id"; "LIB"; "odc_ID"; "Code"
...
- 753
1
vote
1
answer
73
views
Fetch multiple fields in relation_aggregate expression
In the QGIS 3.34+ expression builder, how could one use the expression parameter in the relation_aggregate to fetch multiple fields?
E.g.:
relation_aggregate(
relation:= 'my_relation',
...
- 10.5k
2
votes
0
answers
77
views
QGIS Layer field expression in Polymorphic Relation evaluates to NULL
In QGIS 3.34.3, according to the doc:
Layer expression evaluates to a unique identifier of the layer. This can be the layer name @layer_name, the layer id @layer_id, the layer’s table name decode_uri(...
- 10.5k
0
votes
0
answers
50
views
Using resolved values as a label in child table using only the defined Value Relation
I have a "Value Relation" defined to a parent table from a child one in QGIS 3.34.3:
The attribute table shows the resolved value (species name) correctly:
Same when I use the "...
- 10.5k
0
votes
1
answer
81
views
Setting relations in QGIS not working in QField
I have a set two relation in my QGIS project. One relation called 'Photos' and the other called 'Attitude'. Though in QGIS desktop it seems to work fine but when I transfer it in Qfield it doesn't ...
1
vote
1
answer
138
views
QGIS export layer relations from one project to another
I have a .qgz project with a spatial layer and two non-spatial layers, primarily created for data collection. All the three layers are saved in a single .gpkg file and the non-spatial layers are ...
- 163
2
votes
1
answer
62
views
Getting the result automatically when only one match with Value relation in QGIS
I have a project that comprises three crucial layers:
A SpatiaLite layer named 'HABITATS_POLY'
A layer without geometry named 'CORRESPONDANCES'
A database named "BD_CORINE"
When a code is ...
- 753
2
votes
0
answers
32
views
QGIS not showing cascading relations in identify
I have 3 tables that are related as shown in figure below:
I added two relaltions. The first one between Table1 and Table2 and the other one between Table2 and Table3 as shown in figure below:
On ...
- 83
5
votes
1
answer
170
views
QGIS - many to many relations - query expression
I have a polygon layer with area geometries of parcels and tables with contracts, with owners / users linked by means of a link table in many to many relationships. This is because some parcels may ...
- 537
1
vote
0
answers
72
views
How to set up a filter in a value relation of a child of a parent-layer depending on attributes in parent layer
I have a 1:n relation between (postgresql-) parent-layer "parentlayer" and a child-layer "childlayer" based on parent-layer-field "pl_uuid" referencing child-layer-field &...
- 581
0
votes
0
answers
46
views
QGIS - comma separated values or link table - m-n relations
Is there a way in QGIS to assign multiple values to another value without creating additional columns? Using the example of owners to parcels, I would like to set the reference to several parcels in ...
- 537
1
vote
0
answers
55
views
QGIS values from 1:n related table to parent attribute table
I'm confused since I don't really get the difference between a form and a table in QGIS. I've successfully created multiple one to many relations between my parent shapefile and child excel sheets ...
- 229
1
vote
0
answers
50
views
QGIS: Update parent attribute based on most recent child
To describe the situation, I have parent geopackage layer for 'Trees' which is related to a child geopackage table 'tree_inspections'. So each tree can have many inspections. I use a foreign key '...
- 13
0
votes
1
answer
93
views
Calculate a field in a parent table when a child record is created or modified using QGIS
In QGIS, I have a feature class named "Water_Crossing" that has a field named "Modified".
I have a relation set up from "Water_Crossing" to 3 child tables "...
- 91