How To Fix E2234 - Foreign key &-& can only be changed in the referenced type

SAP Error Message - Details

• Message type: E = Error

• Message class: E2 - DE Data Dictionary

• Message number: 234

• Message text: Foreign key &-& can only be changed in the referenced type

What causes this issue?

You wanted to create or change a foreign key for an expanded field.

System Response

The foreign key for an expanded field is only displayed, but cannot be
changed.

How to fix this error?

Change the foreign key in the referenced type itself. The change also
affects the structures or tables that use this type.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message E2234 - Foreign key &-& can only be changed in the referenced type ?

  The SAP error message E2234, which states "Foreign key &-& can only be changed in the referenced type," typically occurs when you are trying to modify a foreign key relationship in a way that is not allowed by the system. This error is related to the integrity of the data model in SAP, particularly in the context of database tables and their relationships.
  Cause:
  
  Foreign Key Constraint: The error arises when you attempt to change a foreign key field in a table that references another table. The foreign key constraint ensures that the relationship between the two tables remains intact.
  Modification Attempt: You might be trying to change the foreign key field in the child table instead of the parent table (the referenced type). In SAP, changes to foreign key relationships must be made in the table that defines the primary key (the referenced type).
  Data Integrity: SAP enforces data integrity rules to prevent orphaned records or invalid references, which is why it restricts changes to foreign keys.
  
  Solution:
  
  Identify the Tables: Determine which table is the child (the one with the foreign key) and which is the parent (the one with the primary key).
  Modify the Parent Table: If you need to change the foreign key relationship, you should make the necessary changes in the parent table (the referenced type) instead of the child table.
  Check Foreign Key Settings: Review the foreign key settings in the Data Dictionary (SE11) to ensure that they are correctly defined. If you need to change the foreign key definition, do it in the parent table.
  Use Transaction Codes: Use transaction codes like SE11 (Data Dictionary) to view and modify the table definitions and foreign key relationships.
  Consult Documentation: If you are unsure about the changes, consult SAP documentation or seek assistance from a functional consultant who understands the data model.
  
  Related Information:
  
  Data Dictionary (SE11): This is where you can view and manage database tables, including foreign key relationships.
  Foreign Key Relationships: Understanding how foreign keys work in SAP is crucial for maintaining data integrity. Foreign keys link records in one table to records in another.
  SAP Notes: Check SAP Notes for any specific issues or updates related to your version of SAP that might provide additional context or solutions.
  Testing Changes: Always test changes in a development or quality assurance environment before applying them to production to avoid data integrity issues.
  
  By following these guidelines, you should be able to resolve the E2234 error and manage foreign key relationships effectively in SAP.