Here is my situation:
I have created a custom object called "CSB" with fields:
- source_xml__c => Text
- IPN__c => text
- Salesman => Lookupfield to "User"
In the "User" object there is a custom field
- IPN__c => a text field with "external id" checked
What I want to do:
I want to be able to insert a new "CSB" using the built in REST services of SalesForce. This has succeeded by POSTing a JSON string containing al information needed to create a valid "CSB". BUT I had to use the "User's ID" (manually, because this is normally not known in my application) ==> I want to be able to insert a new "CSB" using the external ID "IPN__c" which I do know.
Does anybody have an idea on this one?