小编chr*_*nch的帖子

长时间潜伏,第一个问题!

我正在努力优化此查询,该查询选择与所选过滤器匹配的价格最低的商品:

SELECT product_info.*, MIN(product_all.sale_price) as sale_price, product_all.buy_link
FROM product_info
NATURAL JOIN (SELECT * FROM product_all WHERE product_all.date = '2010-09-30') as product_all
WHERE (product_info.category = 2  
AND product_info.gender = 'W' )
GROUP BY product_all.prod_id
ORDER BY MIN(product_all.sale_price) ASC LIMIT 13

它解释说:

| id | select_type | table        | type   | possible_keys                                             | key     | key_len | ref                 | rows   | Extra                           |  
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+  
|  1 | PRIMARY     | <derived2>   | ALL    | NULL                                                     | NULL    | NULL    | NULL                | …