CREATE TABLE products (product_id NUMBER, parent_product_id NUMBER, product_category_code CLOB, date_product_first_available TIME, date_product_discontinued TIME, product_name CLOB, product_description CLOB, product_price NUMBER)
CREATE TABLE staff (staff_id NUMBER, gender CLOB, first_name CLOB, last_name CLOB, email_address CLOB, phone_number CLOB)
CREATE TABLE complaints (complaint_id NUMBER, product_id NUMBER, customer_id NUMBER, complaint_outcome_code CLOB, complaint_status_code CLOB, complaint_type_code CLOB, date_complaint_raised TIME, date_complaint_closed TIME, staff_id NUMBER)
CREATE TABLE customers (customer_id NUMBER, customer_type_code CLOB, address_line_1 CLOB, address_line_2 CLOB, town_city CLOB, state CLOB, email_address CLOB, phone_number CLOB)

What is the last name of the staff who has handled the first ever complaint?
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
SELECT "t1"."last_name" FROM "staff" "t1" JOIN "complaints" "t2" ON "t1"."staff_id" = "t2"."staff_id" ORDER BY "t2"."date_complaint_raised" FETCH FIRST 1 ROWS ONLY