我有 3 张 table :
Nutritions_facts 表是静态表,包含所有营养的 Nutrition_id 和 Nutrition_ename Products_info 表,其中包含产品信息,列为product_id、product_ename、brand 产品营养事实 这是将产品及其营养成分及其值(value)联系起来的中介表。结构为product_id、nutritional_id、nutritional_value .. 每个产品可以有 1 行或更多行,具体取决于其所含营养成分的数量。 这是一个真实的测试示例
营养事实表
nutrition_id |nutrition_ename
1 | caloreis
2 | fat
3 | sugar
4 | salt
产品信息表
product_id| product_ename | brand
1 | Nutella Hazelnut Cocoa | Nutella
2 | Nutella Jar | Nutella
产品营养事实表
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,返回糖值小于或等于 15、盐值小于或等于 140 的产品名称
我构建了一个返回正确值的查询,但需要很长时间来处理。有人可以建议进行编辑以提高性能吗..
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
)
编辑
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
最佳答案
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)
并执行查询
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'
关于mysql - 在 mysql 中应用多个联接时提高性能,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/35312713/