What must exist in Salesforce for parent records when loading related child records?

The correct approach to loading related records in Salesforce is that parent records must exist before loading child records. This is essential because child records in Salesforce have a relationship with their parent records through a lookup or master-detail relationship. In these relationships, the child record requires a reference to the associated parent record in order to maintain data integrity and establish proper associations within the Salesforce database.

When loading child records, the system needs to know the unique identifier of the parent record so it can assign the child record to the correct parent. If the parent record does not exist beforehand, the child record will not have a valid reference, which can lead to errors or unintended data relationships. This requirement ensures that the hierarchy and relationships established in the data model are accurately followed during data import processes.

In contrast, having child records exist before their respective parents would disrupt this integrity, as the child would not be properly linked to a parent. Loading both parent and child records simultaneously does not account for the sequential dependency that exists between them, and attempting to create parent records after child records would only compound the issue of missing relationships. Hence, the necessity for the parent records to be established first is a fundamental guideline in Salesforce data management.