Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE store ( store_id number, manager_staff_id number, address_id number, last_update time )
TABLE: CREATE TABLE film_text ( film_id number, title text, description text )
TABLE: CREATE TABLE film_category ( film_id number, category_id number, last_update time )
TABLE: CREATE TABLE film_actor ( actor_id number, film_id number, last_update time )
TABLE: CREATE TABLE city ( city_id number, city text, country_id number, last_update time )
TABLE: CREATE TABLE rental ( rental_id number, rental_date time, inventory_id number, customer_id number, return_date time, staff_id number, last_update time )
TABLE: CREATE TABLE film ( film_id number, title text, description text, release_year time, language_id number, original_language_id number, rental_duration number, rental_rate number, length number, replacement_cost number, rating text, special_features text, last_update time )
TABLE: CREATE TABLE address ( address_id number, address text, address2 text, district text, city_id number, postal_code text, phone text, last_update time )
TABLE: CREATE TABLE language ( language_id number, name text, last_update time )
TABLE: CREATE TABLE customer ( customer_id number, store_id number, first_name text, last_name text, email text, address_id number, active boolean, create_date time, last_update time )
TABLE: CREATE TABLE payment ( payment_id number, customer_id number, staff_id number, rental_id number, amount number, payment_date time, last_update time )
TABLE: CREATE TABLE actor ( actor_id number, first_name text, last_name text, last_update time )
TABLE: CREATE TABLE staff ( staff_id number, first_name text, last_name text, address_id number, picture others, email text, store_id number, active boolean, username text, password text, last_update time )
TABLE: CREATE TABLE inventory ( inventory_id number, film_id number, store_id number, last_update time )
TABLE: CREATE TABLE country ( country_id number, country text, last_update time )
TABLE: CREATE TABLE category ( category_id number, name text, last_update time )

### Question ###
What are the first names of customers who have not rented any films after '2005-08-23 02:06:01'?

### Accurate SQL ###

SELECT first_name FROM customer WHERE NOT customer_id IN (SELECT customer_id FROM rental WHERE rental_date > '2005-08-23 02:06:01')