2321355 - Single-valued key cannot be represented as a complex value

while trying to upsert using Odata API , we get the following error message 

"message" : "Single-valued key cannot be represented as a complex value"

Successfactors

In this KBA we are using a sample entity, to reproduce the issue ; please do note this error could be for other entity as well.

Trigger this odata query from any odata rest api client

odata request :

{"__metadata":

{"uri":"Background_Education(userId='1234')"}

,"degree":"567","endDate":"/Date(1388880000000)/","major":"Engineer","school":"test School","startDate":"/Date(1325721600000)/"}

odata response :

{
"d" : [

{ "key" : null, "status" : "ERROR", "editStatus" : null, "message" : "Single-valued key cannot be represented as a complex value", "index" : 0, "httpCode" : 500, "inlineResults" : null }

]
}

This is because, the response is not supplying the required business key to for further execution/upserting of values

• Please trigger the following query - https://apiURL/odata/V2/entityName/$metadata
• apiURL - this URL is specific to the DC you are hosted in
• entityName - the entity you are trying to upsert the data to
• ex : for DC2 - https://apisuccessfactors.eu/odata/V2/Background_Education/$metadata

• From the extracted metadata,please do check for the similar snippet

<EntityType Name="Background_Education">
<Key>
<PropertyRef Name="backgroundElementId"/>
<PropertyRef Name="userId"/>
</Key>

• From the snippet we could see that, backgroundElemetId and userId is the key - hence these two field should be a part of response uri.
• So a well written response would be

{"__metadata":

{"uri":"Background_Education(userId='1234',backgroundElementId='abc')"}

,"degree":"567","endDate":"/Date(1388880000000)/","major":"Engineer","school":"test School","startDate":"/Date(1325721600000)/"}

Single-valued key cannot be represented as a complex value , upsert failure  , KBA , LOD-SF-INT-API , API & Adhoc API Framework , Problem