CDS view &1: Association &2 may use fields of target primary key only.
Message type: E = Error
Message class: SADL_GW_DT_CDS - Messages CDS Checks
Message number: 020
Message text: CDS view &1: Association &2 may use fields of target primary key only.
Self-Explanatory Message
SAP has defined this message as ‘self-explanatory’ and therefore, has not provided any further details for it.
All messages in SAP have a message text (shown above). However, the message text is not always useful enough to understand or resolve the issue.
Therefore, most messages in the SAP system provide additional long text with details about what caused the issue, how it can be resolved, what actions to take or configuration changes to make, etc
Unfortunately, this specific error message does not provide such additional information.
What else can you do?
Even though this error message does not provide any useful or additional message details, you can still try to solve the issue by searching on SAP’s support portal. In many cases, there could be an SAP support note that provides further error explanations or even directions for resolving the error.
Related Error Messages
SADL_GW_DT_CDS019 The composition does not use consistent primary keys.
SADL_GW_DT_CDS018 Enter a valid primary key for CDS view &1.
SADL_GW_DT_CDS021 Key fields of association &2 are missing in CDS view &1.
SADL_GW_DT_CDS022 CDS view &1: Association to child &2 must use primary key of CDS view &1.