How To Fix USMD1B001 - Data model &1: Persistence layer needs to be regenerated

SAP Error Message - Details

• Message type: E = Error

• Message class: USMD1B - Meldungen: MDF Anschluss

• Message number: 001

• Message text: Data model &1: Persistence layer needs to be regenerated

What causes this issue?

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

System Response

How to fix this error?

Activate the data model or import it from the development system or test
system.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message USMD1B001 - Data model &1: Persistence layer needs to be regenerated ?

  The SAP error message USMD1B001 indicates that the persistence layer of a data model needs to be regenerated. This typically occurs in the context of SAP Master Data Governance (MDG) when there are changes made to the data model, such as adding or modifying fields, or when the underlying database structure has changed.
  Cause:
  
  Changes in Data Model: If there have been changes to the data model (like adding new fields or changing existing ones), the persistence layer must be updated to reflect these changes.
  Database Structure Changes: If the underlying database structure has been modified, the persistence layer may also need to be regenerated.
  System Upgrades or Patches: Sometimes, after applying upgrades or patches, the persistence layer may become outdated and require regeneration.
  
  Solution:
  To resolve the error, you need to regenerate the persistence layer for the affected data model. Here are the steps to do this:
  
  Access the Data Model: Go to the relevant transaction in SAP MDG where you can manage data models (usually in the MDG customizing area).
  Regenerate Persistence Layer:
  
  Navigate to the data model that is causing the error.
  Look for an option to regenerate the persistence layer. This is often found in the context menu or as a button in the data model maintenance screen.
  Execute the regeneration process. This will update the database tables and structures to align with the current data model.
  
  
  Check for Errors: After regeneration, check for any errors or warnings that may arise during the process. Address any issues as necessary.
  Test the Changes: Once the persistence layer has been regenerated, test the data model to ensure that it is functioning correctly and that the error message no longer appears.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as MDGIMG for customizing and MDG_MDS for managing master data.
  Documentation: Refer to SAP Help documentation for Master Data Governance for detailed instructions on managing data models and persistence layers.
  Support: If issues persist after regeneration, consider reaching out to SAP support or consulting with your SAP Basis team for further assistance.
  
  By following these steps, you should be able to resolve the USMD1B001 error and ensure that your data model is correctly configured in SAP MDG.