How To Fix OL654 - Key changes not allowed in subtypes

OL654 - Overview

• Message type: E = Error

• Message class: OL - Workflow object types: Run-time system

• Message number: 654

• Message text: Key changes not allowed in subtypes

What causes this issue?

You tried to change the definition of the key fields of a derived type
(create new key field, redefine existing key field, rename / delete
inherited key field).
Subtypes are specializations of the supertype and can therefore appear
at any time in the role of the supertype. For this reason, changes to
key field definitions are not permitted.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Error message extract from SAP system. Copyright SAP SE.

OL654 - Details

• The SAP error message OL654 ("Key changes not allowed in subtypes") typically occurs when you are trying to change the key fields of a subtype in a hierarchical data structure, such as when working with object types in the SAP Business Workflow or when dealing with certain data models in SAP.
  
  Cause:
  
  Key Field Change: The error arises when you attempt to change the key fields of a subtype that is derived from a supertype. In SAP, subtypes inherit characteristics from their supertype, and changing the key fields of a subtype can lead to inconsistencies in the data model.
  Data Integrity: SAP enforces data integrity rules to ensure that the relationships and hierarchies between supertype and subtype are maintained. Changing key fields could violate these relationships.
  
  
  Solution:
  
  Avoid Key Changes: The simplest solution is to avoid changing the key fields of the subtype. If you need to change the key, consider creating a new subtype