Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE staff (last_name VARCHAR, staff_id VARCHAR); CREATE TABLE complaints (staff_id VARCHAR, date_complaint_raised VARCHAR)
### Question:
What is the last name of the staff who has handled the first ever complaint?
### Answer:
SELECT t1.last_name FROM staff AS t1 JOIN complaints AS t2 ON t1.staff_id = t2.staff_id ORDER BY t2.date_complaint_raised LIMIT 1