Salesforce App Builder Practice Exam

The correct answer is that parent objects must have an External ID and Unique attributes. An external lookup relationship is used to link a child external object to a parent Salesforce external object. For this relationship to work, the parent external object must have a field that is defined as an External ID, which allows Salesforce to uniquely identify the records across the external data source. Additionally, the External ID must be marked as unique, ensuring that no two records in the parent object have the same External ID value. This uniqueness is crucial for maintaining data integrity and ensuring proper linking of records.

The other statements do not hold true in the context of external lookup relationships. Lookup filters are not always available for external objects, and cascade-delete functionality is not provided in external object relationships. Furthermore, external lookup relationships can actually link to standard objects, contrary to the misconception that they cannot do so. Understanding these details helps clarify the unique characteristics and requirements of external lookup relationships in Salesforce.