Using MIN value after JOIN MAX(date) MYSQL - mysql

Question

I have 3 table. manufacturers, products and prices
I want to get the last price of product and select min price of them.
Table manufacturers:
# manufacturers
id name
1 Manufacturer 1
2 Manufacturer 2
Table products:
# products
id name
1 Product 1
2 Product 2
Table prices:
# prices
id price manufacturerId createdAt
1 10 1 '2019-09-09 00:00:00'
2 20 1 '2019-09-10 00:00:00'
3 11 2 '2019-09-09 00:00:00'
4 21 2 '2019-09-10 00:00:00'
Full code:
DROP DATABASE if exists ssg ;
CREATE DATABASE ssg;
USE ssg;
# Create database manufacturers
CREATE TABLE manufacturers (id INT(11) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(256) NOT NULL);
# Insert value
INSERT INTO manufacturers (name) VALUES ('Manufacturer 1');
INSERT INTO manufacturers (name) VALUES ('Manufacturer 2');
# Create database products
CREATE TABLE products (id INT(11) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(256) NOT NULL);
# Insert value
INSERT INTO products (name) VALUES ('Product 1');
# Create database prices
CREATE TABLE prices (id INT(11) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
productId INT(11) UNSIGNED NOT NULL,
price BIGINT UNSIGNED NOT NULL,
manufacturerId INT(11) UNSIGNED NOT NULL,
createdAt DATETIME NOT NULL);
# Insert value
INSERT INTO prices (productId, price, manufacturerId, createdAt) VALUES (1, 10, 1, '2019-09-09 00:00:00');
INSERT INTO prices (productId, price, manufacturerId, createdAt) VALUES (1, 20, 1, '2019-09-10 00:00:00');
INSERT INTO prices (productId, price, manufacturerId, createdAt)VALUES (1, 11, 2, '2019-09-09 00:00:00');
INSERT INTO prices (productId, price, manufacturerId, createdAt)VALUES (1, 21, 2, '2019-09-10 00:00:00');
# Query
SELECT products.id, products.name, lastValue.price as latestPrice, lastValue.manufacturerId
FROM products
LEFT JOIN(
SELECT productId, COUNT(DISTINCT manufacturerId) AS total
FROM prices
GROUP BY prices.productId) counts ON counts.productId = products.id
LEFT JOIN (
SELECT prices.*
FROM (
SELECT productId, MAX(createdAt) createdAt
FROM prices
GROUP BY productId) latest
JOIN prices ON latest.productId = prices.productId
AND prices.createdAt = latest.createdAt
) lastValue
ON lastValue.productId = products.id
and I got:
id name latestPrice manufacturerId
1 Product 1 20 1
1 Product 1 21 2
So how can I receive products with only with the MIN of latestPrice.
I have to post it in http://sqlfiddle.com/#!9/418cb7/1 . Please "Build Schema" then "Run SQL"
Sorry for my bad english.

Answer 1

In MySQL 8.0, you can do this with window functions only:
select id, name, price, manufacturerId
from (
select
t.*,
rank() over(order by price) rn2
from (
select
p.id,
p.name,
i.price,
i.manufacturerId,
rank() over(partition by p.id order by i.createdAt desc) rn1
from products p
inner join prices i on i.productId = p.id
) t
where rn1 = 1
) t
where rn2 = 1
This phrases as:
first rank the prices of each product by descending date, and filter on the latest price per product
then rank the all the latest prices by ascending price, and filter on the lowest of them
Demo on DB Fiddle:
id | name | price | manufacturerId
-: | :-------- | ----: | -------------:
1 | Product 1 | 20 | 1