How To Fix MC757 - Selection/join from external field &-&

SAP Error Message - Details

• Message type: E = Error

• Message class: MC - Aggregate: views, matchcodes, lock objects

• Message number: 757

• Message text: Selection/join from external field &-&

What causes this issue?

A join condition links a field of a table which was not included as
base table. This is only permitted in maintaenance views as an
exception, whereby the application program has to ensure that the field
is assigned the correctd values.

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?

For database and help views, only define join conditions for fields of
the base tables. Foreign keys referring to external fields cannot be
used in the definition of join conditions.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message MC757 - Selection/join from external field &-& ?

  The SAP error message MC757 typically occurs in the context of reporting or data extraction, particularly when there is an issue with the selection criteria or joins involving external fields in a query or report. This error indicates that there is a problem with the way the data is being accessed or joined, often due to missing or incorrect field definitions.
  
  Cause:
  
  Field Definition Issues: The external field being referenced may not be defined correctly in the data model or may not exist in the specified context.
  Join Conditions: There may be an issue with the join conditions between tables, especially if the external field is not properly linked to the main data source.
  Data Source Configuration: The data source may not be configured to include the external field, or there may be restrictions on accessing that field.
  Authorization Issues: The user may not have the necessary authorizations to access the external field or the