EXPLAIN EXTENDED SELECT customer.last_name, address.phone
	FROM rental INNER JOIN customer ON rental.customer_id = customer.customer_id
		INNER JOIN address ON customer.address_id = address.address_id
	WHERE address.phone LIKE '19%'\G

*************************** 1. row ***************************
           id: 1
  select_type: SIMPLE
        table: customer
         type: ALL
possible_keys: PRIMARY,idx_fk_address_id
          key: NULL
      key_len: NULL
          ref: NULL
         rows: 541
        Extra:
*************************** 2. row ***************************
           id: 1
  select_type: SIMPLE
        table: address
         type: eq_ref
possible_keys: PRIMARY
          key: PRIMARY
      key_len: 2
          ref: sakila.customer.address_id
         rows: 1
        Extra: Using where
*************************** 3. row ***************************
           id: 1
  select_type: SIMPLE
        table: rental
         type: ref
possible_keys: idx_fk_customer_id
          key: idx_fk_customer_id
      key_len: 2
          ref: sakila.customer.customer_id
         rows: 13
        Extra: Using index
3 rows in set, 1 warning (0.02 sec)