MYSQL order by + group by... fastest way? - mysql

Question

I am trying to optimize a SQL query and I would like some expert opinion on the best/fastest way to combine GROUP BY and ORDER BY
Basically I am trying to select the lowest price from a products table and group them by merchant name.
This was my original query:
select p.*, m.*, d.* from datafeeds as d, products as p left outer join meta as m on p.mykey = m.mykey where p.datafeed_id = d.id and (match(p.name) against ('+asics +"gel" -women*' in boolean mode)) and p.datafeed_id = '35' and p.is_custom = 0 group by d.merchant_name order by d.merchant_name limit 50
And the ORDER BY was not working, I was getting grouped products but not the ones with the lowest prices.
After reading other discussions i came up with an improved query:
SELECT p . * , m . * , d . *
FROM datafeeds AS d, products AS p
INNER JOIN (
SELECT MIN( display_price ) AS MinPrice
FROM products AS p
WHERE 1 =1
AND (
MATCH (
p.name
)
AGAINST (
'+asics +"gel" -women*'
IN BOOLEAN
MODE
)
)
AND p.datafeed_id = '35'
AND p.is_custom =0
GROUP BY merchant_name
) AS p2 ON p.display_price = p2.MinPrice
LEFT OUTER JOIN meta AS m ON p.mykey = m.mykey
WHERE p.datafeed_id = d.id
AND (
MATCH (
p.name
)
AGAINST (
'+asics +"gel" -women*'
IN BOOLEAN
MODE
)
)
AND p.datafeed_id = '35'
AND p.is_custom =0
GROUP BY d.merchant_name
ORDER BY d.merchant_name
LIMIT 50`
The query gets the correct results but it is quite slow.
Is there a better way to do it?
Thanks in advance

Answer 1

You could try this
SELECT p.*,
m.*,
d.*
FROM datafeeds AS d,
(
SELECT *
FROM products
WHERE 1 = 1
AND (
MATCH ( name ) against ( '+asics +"gel" -women*' IN boolean mode ) )
AND datafeed_id = '35'
AND is_custom =0
ORDER BY merchant_name,
display_price) AS p
LEFT OUTER JOIN meta AS m
ON p.mykey = m.mykey
WHERE p.datafeed_id = d.id
GROUP BY d.merchant_name
ORDER BY d.merchant_name
LIMIT 50