3482393 - Error: Instance with the same key already exists

Error when uploading the CBO generated ODATA service.

SAP MARKETING CLOUD

Error message: 'Instance with the same key already exists' while uploading the CBO generated ODATA.

The uniqueness condition was violated for the entries.

You should always make sure that when you are creating new instances via POST requests, no instance already exists for the given values of the key fields.

What might also be helpful is the SAP_UPSERT action which is generated for CBOs:
https://help.sap.com/viewer/0f69f8fb28ac4bf48d2b57b9637e81fa/latest/en-US/07b1d8e18d924f5ba8bf5275e40a3ee4.html

Blog:
https://community.sap.com/t5/crm-and-cx-blogs-by-sap/usage-of-odata-service-of-custom-business-object/ba-p/13309767

Instance with the same key already exists; 400 Bad Request , KBA , CEC-MKT-EXT-CBS , Custom Business Objects in Segmentation , BC-SRV-APS-EXT-BO , Custom Tables and Nodes , Problem