topic Adding Relationship Class to Featue Service in ArcGIS Online Questions

Adding Relationship Class to Featue Service

MarcoPoetsch — Wed, 19 Oct 2022 07:09:54 GMT

Hi there,

I would like to add a relationship class to one of my feature services.

There is already a GlobalID - ParentGLobalID relationship, and want to have second one based on a String (Name - ParentName).

I tried using ArcGIS Pro to achieve this, however,I'm getting this very useless error message here:
https://pro.arcgis.com/en/pro-app/2.9/tool-reference/tool-errors-and-warnings/160001-170000/tool-errors-and-warnings-160251-160275-160270.htm

Is there a way to add this relationship via REST, or any other way?

Re: Adding Relationship Class to Featue Service

Clubdebambos — Wed, 19 Oct 2022 07:55:30 GMT

Hi @MarcoPoetsch

This can be achieved using the ArcGIS Python API similar to below.

Process:

Connect to AGOL
Access Feature Service
Get Layer and Layer ID
Get Table and Table ID (you can also relate to another Layer instead)
Create dictionary for Layer and Table relationships. (the example below shows a one-to-one, you can alter for alternate cardinality)
Update the Layer and Table definitions with the relationship

from arcgis import GIS ## connect to AGOL agol = GIS("home") ## get the feature service using the item id item = agol.content.get("FS_ITEM_ID") ## get the Feature Layer and its ID ## you might need to replace 0 with the proper layer index if more than one layer lyr = item .layers[0] lyr_id = lyr.properties.id ## get the Table and its ID ## you might need to replace 0 with the proper table index if more than one table tbl = item.tables[0] tbl_id = tbl.properties.id ## a dictionary containing the relationship properties for the Feature Layer ## REPLACE LAYER_FIELD with the name of your matching field in the layer lyr_rel_dict = { "name": "Layer_to_Table", "relatedTableId": int(tbl_id), "cardinality": "esriRelCardinalityOneToOne", "role": "esriRelRoleOrigin", "keyField": "LYR_FIELD", "composite": True } ## a dictionary containing the relationship properties for the Table ## REPLACE TABLE_FIELD with the name of you matching field in the table tbl_rel_dict = { "name": "Table_to_Layer", "relatedTableId": int(lyr_id), "cardinality": "esriRelCardinalityOneToOne", "role": "esriRelRoleDestination", "keyField": "TABLE_FIELD", "composite": True } ## update the relationship properties in the Feature Layer and Table lyr.manager.add_to_definition({"relationships" : [lyr_rel_dict]}) tbl.manager.add_to_definition({"relationships" : [tbl_rel_dict]})

Re: Adding Relationship Class to Featue Service

MarcoPoetsch — Thu, 20 Oct 2022 09:41:07 GMT

Sweet. Thanks @Clubdebambos

May I ask you how I would DELETE a relationship class? 🙂

Re: Adding Relationship Class to Featue Service

Clubdebambos — Thu, 20 Oct 2022 10:14:38 GMT

Hi @MarcoPoetsch

I recommend asking this a separate question so it has its own answer and for others to find the answer to it the future.

Re: Adding Relationship Class to Featue Service

MarcoPoetsch — Thu, 20 Oct 2022 10:25:02 GMT

here we go @Clubdebambos
https://community.esri.com/t5/arcgis-online-questions/deleting-relationship-class-from-featue-service/m-p/1223738#M48430