There is a CREATE IF NOT FOUND flag for the IMPORT action. If you create your import file to have a relationship to the parent then it will create that record
Employee.obCompany.Name, Employee.StaffNo, Employee.Name
"Mega Corp", 12345, "Jones, Steve"
If Mega Corp doesn't exist and you use
IMPORT Employee FROM 'c:/mydocuments/importfile.csv' CREATE IF NOT FOUND
It should create that record. You might get duplicates if there are 17 employees that work for Mega Corp as the commit won't happen until later, in which case IN BATCHES OF will help.