How To Fix GG596 - Check the cardinality and the type of the foreign key

SAP Error Message - Details

• Message type: E = Error

• Message class: GG - Messages for FI-SL customizing

• Message number: 596

• Message text: Check the cardinality and the type of the foreign key

What causes this issue?

The cardinality must be 1:CN. You should choose 'Key fields/candidates'
as the foreign key type.

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 GG596 - Check the cardinality and the type of the foreign key ?

  The SAP error message GG596, which states "Check the cardinality and the type of the foreign key," typically occurs in the context of data modeling or database design within SAP systems, particularly when working with the Data Dictionary (DDIC) or when defining relationships between database tables.
  Cause:
  
  
  Cardinality Issues: This error often arises when there is a mismatch in the expected cardinality between the primary key of the parent table and the foreign key in the child table. Cardinality refers to the nature of the relationship between two tables (e.g., one-to-one, one-to-many, many-to-many).
  
  
  Data Type Mismatch: The data types of the foreign key and the primary key must match. If there is a discrepancy in data types (e.g., one is an integer and the other is a string), this error can occur.
  
  
  Missing Foreign Key Definition: If a foreign key relationship is not properly defined in the Data Dictionary, it can lead to this error.
  
  
  Inconsistent Table Definitions: Changes made to the structure of the tables (like adding or removing fields) without properly updating the foreign key relationships can also trigger this error.
  
  
  Solution:
  
  
  Check Cardinality: Review the relationship between the tables involved. Ensure that the cardinality defined in the foreign key matches the actual relationship. For example, if the parent table can have multiple entries corresponding to a single entry in the child table, the foreign key should reflect a one-to-many relationship.
  
  
  Verify Data Types: Ensure that the data types of the foreign key in the child table and the primary key in the parent table are identical. If they are not, you may need to adjust the data type of one of the fields.
  
  
  Define Foreign Key Properly: If the foreign key is not defined, you need to create it in the Data Dictionary. Use transaction codes like SE11 (Data Dictionary) to define the foreign key relationship correctly.
  
  
  Check for Table Changes: If there have been recent changes to the table structures, ensure that all foreign key relationships are updated accordingly. You may need to regenerate the database objects or activate the tables again.
  
  
  Use Transaction Codes: Utilize transaction codes like SE11 to check the definitions of the tables and their relationships. You can also use SE14 to check and adjust database objects.
  
  
  Related Information:
  
  Documentation: Refer to SAP Help documentation for detailed guidelines on defining foreign keys and understanding cardinality.
  Data Dictionary (SE11): This is the primary tool for managing database objects in SAP. You can view and edit table definitions, including foreign key relationships.
  Database Consistency: Regularly check for database consistency and integrity, especially after making changes to table structures.
  
  By following these steps, you should be able to resolve the GG596 error and ensure that your foreign key relationships are correctly defined and functioning as intended.