How To Fix USMD1557 - Data model &1: Key attributes must not be assigned to entity type &2

USMD1557 - Overview

• Message type: E = Error

• Message class: USMD1 - Datenmodel

• Message number: 557

• Message text: Data model &1: Key attributes must not be assigned to entity type &2

What causes this issue?

The &V3& attribute is defined as key field. This is not allowed for
attributes of entity types of storage and usage type 4.

System Response

The system does not save or activate the data model.

How to fix this error?

In the <LS>Attributes </>view, deselect <LS>Key Field</> for the &V3&
attribute.
If you want to create a key field for the &V2& entity type, choose the
<LS>Relationships </>view.

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.

USMD1557 - Details

• The SAP error message USMD1557 indicates that there is an issue with the assignment of key attributes in a data model. Specifically, it states that key attributes must not be assigned to a certain entity type. This error typically arises in the context of SAP Master Data Governance (MDG) or similar data modeling scenarios.
  
  Cause:
  The error occurs when you attempt to assign key attributes to an entity type that does not support them. In SAP data modeling, key attributes are used to uniquely identify instances of an entity. However, certain entity types may not be designed to have key attributes, leading to this error.
  
  Solution:
  To resolve the error USMD1557, you can follow these steps:
  
  
  Review the Entity Type: Check the entity type mentioned in the error message. Ensure that it is appropriate for key attributes. Some entity types may be designed to have only non-key attributes.
  
  
  Modify the Data Model:
  
  If the entity type is