SAP RAP Custom entity referential constraint error with composition and @OData.property.name

[altafmohammedaftab]

Hi Community,

I'm currently working on an SAP RAP unmanaged scenario using Custom Entities in ABAP Cloud, and I’ve run into an issue when trying to expose metadata.

Scenario:

I have two custom entities defined as follows:

---

Root Entity:

 

@EndUserText.label: 'Custom Root entity for Parent'
define root custom entity ZParent {
  @OData.property.name: 'SessionId'
  key SESSION_ID : abap.int1;

  _Child : composition [1..1] of ZChild;
}

Child Entity:

 

@EndUserText.label: 'Custom entity for Child'
define custom entity ZChild {
  @OData.property.name: 'SessionId'
  key SESSION_ID : abap.int1;

  _Parent : association to parent ZParent on _Parent.SESSION_ID = $projection.SESSION_ID;
}

---

Issue:

When I try to access the $metadata of the service, I receive the following error:

Code: SY/530  
Message: Association assoc_0FCF7701A629F6O035FFE9E6E21380F1: referential constraint property not found in entity ZChildType.

Interestingly, the error does not occur when the @odata.property.name annotation is removed.

---

Question:

Does the RAP framework not automatically handle property name mapping when using @odata.property.name?

Is there an annotation or recommended approach to handle referential constraints in this case?

---

Any insights or guidance would be greatly appreciated!

Thanks & Regards,
Aftab

[junwu]

do you really have to use that annotation? just avoid it if it is not necessary.

[lbreddemann]

There is no global "read only mode" switch for application users.

One option I can think off is to create a roles-model that differentiates between reading and writing.

To disable writing you could then revoke the data change privileges from the writing role(s).