How To Fix GH302 - Field & is not allowed for defining foreign keys

SAP Error Message - Details

• Message type: E = Error

• Message class: GH - Help functions and tools in FI-SL

• Message number: 302

• Message text: Field & is not allowed for defining foreign keys

What causes this issue?

Field &V1& is maintained by SAP and it is not recommended that you use
this field to define foreign keys.

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.

Smart SAP Assistant

• What is the cause and solution for SAP error message GH302 - Field & is not allowed for defining foreign keys ?

  The SAP error message GH302, which states "Field & is not allowed for defining foreign keys," typically occurs when you are trying to define a foreign key relationship in a database table, but the field you are attempting to use does not meet the necessary criteria for foreign key definitions.
  Cause:
  
  Field Type: The field you are trying to use as a foreign key may not be of a compatible data type with the primary key of the referenced table.
  Field Attributes: The field may not have the required attributes (e.g., it might not be a key field or it may not be defined as a unique field).
  Technical Settings: The technical settings of the field may not allow it to be used as a foreign key.
  Field Length: The length of the field may not match the length of the corresponding primary key field in the referenced table.
  Domain Issues: The field may be based on a domain that does not allow foreign key relationships.
  
  Solution:
  
  Check Field Compatibility: Ensure that the field you are trying to use as a foreign key has the same data type and length as the primary key in the referenced table.
  Review Field Attributes: Make sure that the field is defined correctly in the data dictionary (SE11) and has the necessary attributes to be used as a foreign key.
  Adjust Technical Settings: If necessary, modify the technical settings of the field to allow it to be used as a foreign key.
  Use a Different Field: If the current field cannot be used as a foreign key, consider using a different field that meets the requirements.
  Check Domain and Data Element: Ensure that the domain and data element associated with the field allow for foreign key relationships.
  
  Related Information:
  
  Transaction Codes: You can use transaction codes like SE11 (Data Dictionary) to check the definitions of the fields and tables involved.
  Documentation: Refer to SAP documentation for guidelines on defining foreign keys and the requirements for fields.
  SAP Notes: Check SAP Notes for any known issues or additional guidance related to this error message.
  Testing: After making changes, test the foreign key relationship to ensure it is functioning as expected.
  
  If you continue to experience issues after following these steps, consider reaching out to your SAP support team or consulting with an SAP expert for further assistance.