Questions tagged [relation]
The relation tag has no usage guidance.
48
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Storing OSM relations correctly as geometry in BQ
I am looking at the best/efficient way to decompose OSM relations and store as geography, currently I am using:
https://raw.githubusercontent.com/tyrasd/osmtogeojson/gh-pages/osmtogeojson.js
to ...
- 20.2k
1
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2
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358
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Geometry extraction from osm.pbf file using relation id with ogr2ogr
What works
If I need a GeoJSON file with the OpenStreetMap borders of Liechtenstein, I download liechtenstein-latest.osm.pbf from GeoFabrik:
curl https://download.geofabrik.de/europe/liechtenstein-...
- 2,224
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18
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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
1
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138
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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
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38
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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
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1
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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
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0
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77
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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
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50
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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
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84
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QGIS relation reference widget filter between child (point layer) and parent table (no geometry)
I have two PostGIS layers in QGIS 3.28, they are in a 1-N relation (association):
layer A (parent) without geometry (table)
layer B (child) with point geometry
Both A and B layers have the codsede ...
- 65.2k
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81
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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 ...
- 1,846
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11
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Project Sync-ing doesn't work in tablet as in the phones Qfield app
I have a project in QGIS and I'd made some relations in it, but one of (a non geometric layer, named Evaluate, which is based on a Vector layers (point) order number. This layer contains trees) those ...
- 20.2k
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
12
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3
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750
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Handling multiple selections result in "Value Relation Widget" in QGIS
Using the "Allow multiple selections" in the "Value Relation Widget" results in {value1,value2,...}. But arrays in QGIS are written like ['value1','value2',...].
How do I handle ...
- 1,726
2
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1
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437
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Extracting relations with osmnx?
I am using osmnx package https://osmnx.readthedocs.io/en/stable/osmnx.html
to extract data from OSM. I aim to obtain relations from the cyclist node network in Flanders. After some info about tagging, ...
CommunityBot
- 1
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82
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QGIS relation reference widget shows an empty list instead of values
I'm trying to set up a QField project to entry data from a bird watch project.
I have a few layers which I would like to connect with the ID of the tour.
I am using relation reference widgets.
The ...
- 366