Question

我有3张桌子：

Nutritions_facts表是具有所有营养营养_id和营养_ename的静态表 Products_info表包含产品信息，列为product_id，product_ename，brand product_nutrition_facts 这是一个中介表，它将产品与营养成分与价值联系起来。结构是product_id，nutrition_id，营养价值。根据营养成分的数量，每个产品可以有1行或更多。这是一个真实的测试示例

Nutrition_facts表

 nutrition_id |nutrition_ename
       1 | caloreis    
       2 | fat    
       3 | sugar    
       4 | salt

Products_info表

product_id| product_ename           | brand   
    1 | Nutella Hazelnut Cocoa | Nutella    
    2 | Nutella Jar            | Nutella

product_nutrition_facts表

product_id | nutrition_id | nutrition_value
     1 |            1 |             200
     1 |            2 |              15
     1 |            3 |               2
     1 |            4 |              11
     2 |            1 |             200
     2 |            2 |              15
     2 |            3 |              12
     2 |            4 |              11

我需要进行查询，返回产品名称，其中糖的值小于或等于15，盐小于或等于140

我构建了一个返回正确值的查询，但需要很长时间才能处理。有人可以建议编辑以提高性能，请...

SELECT DISTINCT p.product_id, p.brand, p.e_name, p.image_low
FROM products_info p
JOIN product_nutrition_facts pn ON p.product_id = pn.product_id
WHERE p.brand =  'AL MARAI'
AND (
(
p.product_id
IN (

SELECT product_id
FROM product_nutrition_facts pn
WHERE pn.nutrition_id =3
AND pn.nutrition_value <=15
)
 )
 AND (
 p.product_id
IN (

SELECT product_id
FROM product_nutrition_facts pn
WHERE pn.nutrition_id =4
AND pn.nutrition_value <=140
)
)
)
AND (
pn.nutrition_id =3
OR pn.nutrition_id =4
)

EDITS

 CREATE TABLE `products_info` (
 `product_id` int(11) NOT NULL AUTO_INCREMENT,
 `image_low` varchar(400) DEFAULT NULL,
  `e_name` varchar(200) DEFAULT NULL, 
 PRIMARY KEY (`product_id`),
 UNIQUE KEY `product_id_UNIQUE` (`product_id`)
) ENGINE=InnoDB AUTO_INCREMENT=249292 DEFAULT CHARSET=utf8


CREATE TABLE `product_nutrition_facts` (
 `prod_nut_id` int(11) NOT NULL AUTO_INCREMENT,
 `product_id` int(11) DEFAULT NULL,
 `nutrition_id` int(11) DEFAULT NULL,
 `nutrition_value` varchar(25) DEFAULT NULL,
 `unit_id` int(11) DEFAULT NULL,
 `parent` int(11) DEFAULT NULL,
 `serving_size` varchar(145) DEFAULT NULL,
 `serving_size_unit` int(11) DEFAULT NULL,
 `no_nutrition_facts` int(11) NOT NULL,
 `added_by` varchar(145) DEFAULT NULL,
 `last_update` timestamp NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
 `inserted_time` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
 `updated_by` varchar(150) NOT NULL,
 PRIMARY KEY (`prod_nut_id`),
 UNIQUE KEY `prod_nut_id_UNIQUE` (`prod_nut_id`),
 KEY `nutrition_id_fk_idx` (`nutrition_id`),
 KEY `unit_Fk_idx` (`unit_id`),
 KEY `unit_fk1_idx` (`serving_size_unit`),
 KEY `product_idFK` (`product_id`)
) ENGINE=InnoDB AUTO_INCREMENT=580809 DEFAULT CHARSET=utf8

 CREATE TABLE `nutrition_facts` (
 `nutrition_id` int(11) NOT NULL AUTO_INCREMENT,
 `nutrition_aname` varchar(145) DEFAULT NULL,
 `nutrition_ename` varchar(145) DEFAULT NULL,
 `alternative_name` varchar(145) DEFAULT NULL,
  `unit` varchar(8) NOT NULL,
 `daily_value` int(11) NOT NULL,
 `nut_order` int(2) NOT NULL,
 `is_child` int(1) NOT NULL,
 `last_update` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
 PRIMARY KEY (`nutrition_id`)
 ) ENGINE=InnoDB AUTO_INCREMENT=53 DEFAULT CHARSET=utf8

Answer 1

尝试添加索引product_nutrition_facts (nutrition_id,nutrition_value,product_id)，product_nutrition_facts (product_id,nutrition_id,nutrition_value)，products_info (brand)和支持查询

SELECT p.*
FROM products_info p
join product_nutrition_facts pn1 on
  pn1.product_id=p.product_id
  AND pn1.nutrition_id=3
  AND pn1.nutrition_value<=15
join product_nutrition_facts pn2 on
  pn2.product_id=p.product_id
  AND pn2.nutrition_id=4
  AND pn2.nutrition_value<=140
where
  p.brand =  'AL MARAI'

Answer 2

IN ( SELECT ... ) - 不能很好地优化;变成JOIN（正如马克斯建议的那样）

＆＃34; Overnormalization＆＃34; - Nutrition_facts可以被删除;只需使用nutrition名称代替nutrition _id。

在mysql中应用多个连接时增强性能

2 个答案: