Combine latest records with table - mysql

Question

I am using mysql and I am having the following two tables:
Products:
| id | name |
|----|-----------|
| 1 | Product 1 |
| 2 | Product 2 |
| 3 | Product 3 |
Prices:
| id | Product_id | created_at | prices |
|----|------------|---------------------|--------|
| 1 | 1 | 2017-12-23 08:32:11 | 10 |
| 2 | 1 | 2017-11-21 03:33:10 | 12 |
| 3 | 2 | 2017-12-23 08:32:11 | 43 |
| 4 | 2 | 2017-11-21 03:33:10 | 23 |
| 5 | 3 | 2017-12-23 08:32:11 | 78 |
| 6 | 3 | 2017-11-21 03:33:10 | 34 |
If I do:
SELECT * FROM prices WHERE prices.id IN ( SELECT MAX(prices.id) FROM prices GROUP BY prices.created_at )
This gives me the last prices for each product_id:
| id | Product_id | created_at | prices |
|----|------------|---------------------|--------|
| 1 | 1 | 2017-12-23 08:32:11 | 10 |
| 3 | 2 | 2017-12-23 08:32:11 | 43 |
| 5 | 3 | 2017-12-23 08:32:11 | 78 |
I would like to have as final result all Products with the latest prices, which would look like the following:
| id | name | product_id | created_at | prices |
|----|-----------|------------|---------------------|--------|
| 1 | Product 1 | 1 | 2017-12-23 08:32:11 | 10 |
| 2 | Product 2 | 2 | 2017-12-23 08:32:11 | 43 |
| 3 | Product 3 | 3 | 2017-12-23 08:32:11 | 78 |
However, I am not sure how to combine:
select * from products
and
SELECT * FROM prices WHERE prices.id IN ( SELECT MAX(prices.id) FROM prices GROUP BY prices.created_at )
I highly appreciate your replies!

Answer 1

Assuming your first query is giving you expected result, just use join.
SELECT p.*,d.name FROM prices p
inner join product d
on d.id=p.product_id
WHERE
p.id IN
( SELECT MAX(prices.id) FROM prices GROUP BY prices.created_at )
If you believe that there are product id in price which are not mapped in product then use left join instead of inner join.

Answer 2

I think you have get max total price with product name so below is query according your given tables
select prices.id, products.id,products.product, sum(prices.prices) as Totalprices from prices join products on prices.id=products.id group by prices.id order by Totalprices desc limit 1
Hope it help you

Answer 3

Assuming that the latest prices are the most recent created ones and depicted by prices.created_at value, to get the latest prices you could better rely on prices.created_at, instead of assuming chronological ordering by mean of prices.id (autoincrement), as in:
SELECT products.id, products.name, prices.created_at, prices.prices
FROM products
INNER JOIN prices ON products.id=prices.product_id
INNER JOIN
(SELECT product_id, MAX(created_at) AS created_at FROM prices GROUP BY product_id) AS LATEST_PRICES
on prices.product_id=LATEST_PRICES.product_id
-- WHERE prices.created_at = LATEST_PRICES.created_at
AND prices.created_at = LATEST_PRICES.created_at