How To Fix CNV_00001256 - All fields of table &1 are filled by the field mapping of table &2

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_00001 - Message class for CWB settings maintenance programs

• Message number: 256

• Message text: All fields of table &1 are filled by the field mapping of table &2

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_00001256 - All fields of table &1 are filled by the field mapping of table &2 ?

  The SAP error message CNV_00001256 indicates that all fields of a specified table (denoted as &1) are filled by the field mapping of another table (denoted as &2). This error typically arises during data migration or conversion processes, particularly when using SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or the SAP Data Services.
  Cause:
  The error occurs when:
  
  The target table (&1) is being populated with data from the source table (&2), but the mapping configuration is such that all fields in the target table are being filled from the source table.
  This situation may arise due to incorrect or incomplete field mapping configurations, where the system expects certain fields to be populated differently or not at all.
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Review Field Mapping:
  
  Check the field mapping configuration between the source and target tables. Ensure that the mapping is set up correctly and that it aligns with the data model of the target table.
  
  
  
  Adjust Mapping:
  
  If all fields of the target table are being filled from the source table, consider whether this is the intended behavior. If not, adjust the mapping to ensure that only the necessary fields are populated.
  
  
  
  Check for Required Fields:
  
  Ensure that any required fields in the target table are being populated correctly. If certain fields should remain empty, make sure they are not being inadvertently filled by the mapping.
  
  
  
  Consult Documentation:
  
  Refer to SAP documentation or guides related to the specific data migration tool you are using. There may be specific instructions or best practices for setting up field mappings.
  
  
  
  Testing:
  
  After making adjustments, perform a test migration to verify that the error no longer occurs and that the data is being populated as expected.
  
  
  
  Seek Support:
  
  If the issue persists, consider reaching out to SAP support or consulting with a technical expert who specializes in data migration.
  
  
  
  Related Information:
  
  Transaction Codes: Depending on the tool you are using, you may need to use specific transaction codes to access the data migration settings (e.g., LTMC for the Migration Cockpit).
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional guidance on data migration issues.
  Community Forums: Engage with SAP community forums or user groups where similar issues may have been discussed, and solutions shared.
  
  By following these steps, you should be able to identify the root cause of the error and implement a solution to resolve it.