How To Fix UD646 - Unbundling of the relationships was switched on

SAP Error Message - Details

• Message type: E = Error

• Message class: UD - EDM - Enterprise Data Model

• Message number: 646

• Message text: Unbundling of the relationships was switched on

What causes this issue?

The semantic attributes of the foreign key relationships are symbolized
by different entries and by arrows with this setting. The
representation corresponds to that for relationships in the SAP data
model.
Unbundling relationships:
Entry from the left:
* Relationships of type KEY ( foreign key fields are specified as
key fields/candidates )
* Relationships of type TXT ( foreign key fields are specified as
key fields of a text table )
Entry from above/below:
* Relationships of type REF ( foreign key fields are specified as
non-key fields/candidates )
* Relationships whose foreign key fields are not specified
Arrows:
The arrows symbolize the right cardinality:
* single arrow: cardinality 1
* single arrow with vertical line: cardinality C
* double arrow: cardinality N
* double arrow with vertical line: cardinality CN
* no arrow: cardinality not speicified
The text for the left cardinality is displayed on the relationship line
if it is not equal to 1.

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.