To add new rows to a data extension while keeping existing data intact, a Primary Key is necessary to uniquely identify each row. This ensures that Salesforce Marketing Cloud can insert new records without overwriting existing ones, preserving data integrity and supporting proper data management during imports.
* Why Primary Key is Required: The Primary Key prevents duplicate records and enables the system to distinguish between existing and new rows based on unique identifiers.
* Salesforce Documentation Reference: Refer to Data Extension Keys and Constraints for more details on how primary keys function in data extensions.