Final answer:
The question involves completing a SQL join query for distinct customer and rental data, sorted by residence city and checkout date. The provided example fills in the necessary conditions for the joins and sorting.
Step-by-step explanation:
The student is asking how to complete a SQL join query that selects distinct values from columns in two different tables, linking them with specified conditions. To fill in the blanks, we need to specify the join conditions, such as customer.customer_id = rentals.customer_id and rentals.rental_id = rentcost.rental_id. The order by clause is used to sort the results. To complete this query, one might write:
SELECT DISTINCT customer.resid_city, customer.birthplace, rentals.data_out, rentals.data_returned, rental.return_city
FROM customer
JOIN rentals ON customer.customer_id = rentals.customer_id
JOIN rentcost ON rentals.rental_id = rentcost.rental_id
ORDER BY customer.resid_city, rentals.data_out;
This will yield a list of unique customer residence cities, birthplaces, rental checkout and return dates, and rental return cities, sorted first by the customer's residence city and then by the date the rental was checked out.