Trying to perform inline 'insertion' of data in Successfactors using Odata API
You want to use Merge operation for the same since you do not want to pass all the fields marked as 'Required=true' for that entity
MERGE operation does not support 'Inline structure' of data.
In the ODATA specification only insert operation supports inline structure. MERGE/REPLACE doesn't.
But our 'Upsert' operation also supports insertion of data with 'inline entries' so you can use either of Insert/Upsert operation to perform the 'Inline entity' upsert.
SFOData support for Inline entity structure
SAP SuccessFactors HCM Suite all versions