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group by - MySQL Left Join + Min

Seemingly simple MySQL question, but I've never had to do this before..

I have two tables, items and prices, with a one-to-many relationship.

Items Table
id, name

Prices Table
id, item_id, price

Where

prices.item_id = items.id

What I have so far:

SELECT items.id, items.name, MIN(prices.price)
FROM items
LEFT JOIN prices ON items.id = prices.item_id
GROUP BY items.id

How do I also return the corresponding prices.id for that minimum price? Thanks!

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1 Answer

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This will return multiple records for a record in Items if there are multiple Prices records for it with the minimum price:

select items.id, items.name, prices.price, prices.id
from items
left join prices on (
    items.id = prices.item_id 
    and prices.price = (
        select min(price)
        from prices
        where item_id = items.id
    )
);

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