How To Fix FDT_DSM023 - Custom expression types (&1) are not allowed in remote services

SAP Error Message - Details

• Message type: E = Error

• Message class: FDT_DSM - BRFplus: Decision Service Manager

• Message number: 023

• Message text: Custom expression types (&1) are not allowed in remote services

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message FDT_DSM023 - Custom expression types (&1) are not allowed in remote services ?

  The SAP error message FDT_DSM023 indicates that there is an issue with the use of custom expression types in remote services within the SAP system. This error typically arises when you are trying to use a custom expression type in a context where it is not supported, particularly in remote service calls.
  Cause:
  The primary cause of this error is the attempt to use custom expressions or custom data types in a remote service context. SAP's remote services have certain restrictions, and custom expressions are not allowed due to serialization and compatibility issues. This is often encountered in scenarios involving:
  
  Data extraction or transformation processes.
  Remote Function Calls (RFC) or OData services that are trying to utilize custom logic or expressions.
  
  Solution:
  To resolve the FDT_DSM023 error, consider the following steps:
  
  
  Review Custom Expressions: Check the custom expressions you are using in your service. If they are not essential, consider removing or replacing them with standard expressions that are supported in remote contexts.
  
  
  Use Standard Data Types: Ensure that you are using standard data types and expressions that are compatible with remote services. This may involve refactoring your logic to avoid custom types.
  
  
  Modify Service Logic: If the custom expression is necessary, you may need to modify the service logic to handle the data processing locally before sending it to the remote service.
  
  
  Check Service Configuration: Review the configuration of the remote service to ensure that it is set up correctly and that it adheres to the limitations regarding custom expressions.
  
  
  Consult Documentation: Refer to the SAP documentation for the specific version you are using to understand the limitations and best practices for using expressions in remote services.
  
  
  Testing: After making changes, thoroughly test the service to ensure that it functions correctly without the custom expressions.
  
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may provide additional insights or updates regarding this error.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they have implemented.
  SAP Support: If the issue persists, consider reaching out to SAP Support for assistance, especially if this is impacting critical business processes.
  
  By following these steps, you should be able to address the FDT_DSM023 error and ensure that your remote services function correctly without the use of unsupported custom expression types.