Оптимизация (30 мин.)

Смотреть код

select
*
from
film;

explain analyze
select
*
from
film;

explain analyze
select
*
from
film
where
length > 150;

explain analyze
select
*
from
film
where
length > 180;

create index film_length_idx on
film(length);

drop index film_length_idx;

-- min index scan

-- middle bitmap index scan

-- max seq scan

explain analyze
select
f.title,
p.amount
from
film f
join inventory i
using(film_id)
join rental r
using(inventory_id)
join payment p
using(rental_id);