How To Fix TG143 - Changes made to fields of this table are reset by the upgrade

SAP Error Message - Details

• Message type: E = Error

• Message class: TG - Messages for Upgrade Repository Switch

• Message number: 143

• Message text: Changes made to fields of this table are reset by the upgrade

What causes this issue?

In an R/3 Release lower than 3.0A, the definition of a table has been
modified that, as of Release 3.0, belongs to the 'central basis' group.
These tables cannot be modified. The modification therefore has to be
reset.

System Response

To prevent data loss, the upgrade stops as a result of this error
message.

How to fix this error?

The modifications are not usually kept since they are already contained
in the new standard, or they may have unpredictable consequences for
performance of the SAP system. In certain cases, the corresponding table
may have wrongly been included in the class of the central basis which
means that the modification must not be overwritten. The following
documentation explains possible procedures for one modification.
Case 1: The modification is a preliminary correction
----------------------------------------------
If there are no additional, critical modifications, ignore the error
message. You do not need a password to continue the upgrade by choosing
'ignore'. In transaction SPDD (modification adjustments), later reset
the table to the SAP Standard.
Case 2: No changes were made to the structure
--------------------------------------------------------------
The field description of the table was not modified; that is, no fields
were added or deleted, and no field lengths or types were changed.
Instead, the buffer properties were modified. In this case, you can
ignore the error message since the modification can subsequently be
created again without causing loss of data. Include this modification
again in transaction SPDD.
Case 3: The structure of the table was changed
------------------------------------------------
If the table exists in the database, and you choose to ignore the error
message, this causes loss of data. In time-critical situations, SAP
recommends that you copy the data to the customer namespace and then
include the modification with the help of SAP after the upgrade. It is
better to inform the 2nd Level Hotline for the upgrade procedure. The
hotline employees have to check whether the table is classified
correctly. If it does not belong to the central basis, there is a
procedure available for changing this classification individually. Of
course we intend to correct this error for the next release.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message TG143 - Changes made to fields of this table are reset by the upgrade ?

  The SAP error message TG143 indicates that changes made to fields of a specific table are being reset due to an upgrade. This typically occurs when the system detects that modifications have been made to standard SAP tables, and during an upgrade, these changes may be overwritten or reset to their original state as defined by the new version of the software.
  Cause:
  
  Modification of Standard Tables: The error usually arises when a customer has made modifications to standard SAP tables (e.g., adding fields, changing data types) that are not compatible with the new version of the software being upgraded.
  Upgrade Process: During the upgrade, SAP applies its own changes to the database schema, which can lead to the resetting of any custom changes made to the standard tables.
  
  Solution:
  
  Review Modifications: Before performing an upgrade, review all modifications made to standard tables. Document these changes thoroughly.
  Use Custom Tables: Instead of modifying standard tables, consider creating custom tables or using append structures to add fields. This approach helps avoid conflicts during upgrades.
  SAP Notes: Check for any relevant SAP Notes that may provide guidance on handling specific tables or fields that are affected by the upgrade.
  Backup and Restore: If changes are lost during the upgrade, you may need to restore them from a backup or reapply them manually after the upgrade is complete.
  Testing: Conduct thorough testing in a sandbox or development environment before applying the upgrade to the production system. This allows you to identify potential issues and address them proactively.
  
  Related Information:
  
  SAP Upgrade Guide: Refer to the official SAP upgrade guide for best practices and recommendations on handling customizations during upgrades.
  SAP Community: Engage with the SAP Community forums to seek advice from other users who may have encountered similar issues.
  Change Management: Implement a change management process to track modifications to standard tables and ensure that they are documented and reviewed before upgrades.
  
  By following these steps, you can mitigate the impact of the TG143 error and ensure a smoother upgrade process.