解决 SQL 问题绝对能让你对 MySQL 的理解更进一步！-木庄网络博客

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SQL教程栏目介绍如何更有效理解MySQL

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属性表(product_props)结构如下

数据量800W以上

字段名	类型	说明
id	int	id
pn_id	int	属性类型
pv_id	int	属性值
product_id	int	产品ID

其中product_id与pn_id,pv_id是一对多的关系。
数据类似这样:

product_id	pn_id	pv_id
10970	5 （型号）	135 （苹果9）
10970	11 （内存）	23 （512G）
10970	10 （颜色）	17 （土豪金）
10970	8 （网络）	6（5G）
10980	5	135
10980	11	24 （1024G）
10980	10	16 （极光蓝）

产品表(product)结构如下

数据量40W以上

字段名	类型	说明
product_id	int	product_id
type_id	int	类型id
brand_id	int	品牌id
model_id	int	型号id
status	tinyint	状态

数据类似以下：

product_id	type_id	brand_id	model_id	status
10970	1（手机）	1(苹果)	1(Iphone8)	1(正常)
10980	1（手机）	1(苹果)	1(Iphone8X)	3(已售)
10981	1（手机）	1(苹果)	1(Iphone8XP)	1(正常)

问题

找出型号为苹果9同时内存为512G，颜色为土豪金，状态为正常的产品总数，
ps : 属性条件可能会有超过10组。

要求

性能第一，杜绝聚合函数等

原问题的解决方案性能排行

来自 @Kamicloud的 exist方案

SELECT 
    sql_no_cache `product_id`
FROM
    `zx_tests` AS a
WHERE
    `pn_id` = 101 AND `pv_id` = 59
        AND EXISTS( SELECT 
           sql_no_cache  *
        FROM
            `zx_tests`
        WHERE
        a.product_id = product_id and
            `pn_id` = 101 AND `pv_id` = 171);
 
    2 组条件下 0.657，3 组 0.695，4 组 0.759，5 组 0.743 （单独查属性表）

来自 @Elijah_Wang的子查询方案

SELECT `product_id` FROM `product` WHERE `pn_id` = 5 AND `pv_id` = 135 AND `product_id` IN (SELECT `product_id` FROM `product` WHERE `pn_id` = 11 AND `pv_id` = 23);
 
    2 组条件下 0.729，3 组 0.75，4 组 0.730，5 组 0.757 (新问题之前)

新问题之后的性能排行

来自 @Elijah_Wang的子查询方案

select SQL_NO_CACHE count(1) from pdi_product a join  (
    SELECT
         distinct product_id
    FROM
        `product_props` 
    WHERE
        `pn_id` = 5 
        AND `pv_id` = 127
        AND `product_id` IN ( SELECT  `product_id` FROM `product_props` WHERE `pn_id` = 11 AND `pv_id` = 22 ) 
        AND `product_id` IN ( SELECT  `product_id` FROM `product_props` WHERE `pn_id` = 10 AND `pv_id` = 18 ) 
        AND `product_id` IN ( SELECT  `product_id` FROM `product_props` WHERE `pn_id` = 8 AND `pv_id` = 6 )  
        AND `product_id` IN ( SELECT  `product_id` FROM `product_props` WHERE `pn_id` = 9 AND `pv_id` = 1 )
        ) b on a.product_id = b.product_id 
        where  a.status = 1；

耗时1.5-1.56 （执行10次的范围）

expain分析：

SQL 性能实战来了，机不可失！

select SQL_NO_CACHE count(1) from pdi_product a 
    where  a.status = 1 and a.product_id in (SELECT
     distinct product_id
FROM
    `product_props` 
WHERE
    `pn_id` = 5 
    AND `pv_id` = 127
    AND `product_id` IN ( SELECT  `product_id` FROM `product_props` WHERE `pn_id` = 11 AND `pv_id` = 22 ) 
    AND `product_id` IN ( SELECT  `product_id` FROM `product_props` WHERE `pn_id` = 10 AND `pv_id` = 18 ) 
    AND `product_id` IN ( SELECT  `product_id` FROM `product_props` WHERE `pn_id` = 8 AND `pv_id` = 6 )  
    AND `product_id` IN ( SELECT  `product_id` FROM `product_props` WHERE `pn_id` = 9 AND `pv_id` = 1 ))

耗时0.69-0.72（执行10次的范围）

explain分析：

来自 @Kamicloud的 exist方案

SELECT SQL_NO_CACHE
        count(1) 
    FROM
        product a
    WHERE
        a.STATUS = 1 
        AND a.product_id IN (
    SELECT DISTINCT
        `product_id` 
    FROM
        `product_props` AS a 
    WHERE
        a.`pn_id` = 5 
        AND a.`pv_id` = 127 
        AND EXISTS ( SELECT product_id FROM `product_props` WHERE a.product_id = product_id AND `pn_id` = 11 AND `pv_id` = 22 ) 
        AND EXISTS ( SELECT product_id FROM `product_props` WHERE a.product_id = product_id AND `pn_id` = 10 AND `pv_id` = 18 ) 
        AND EXISTS ( SELECT product_id FROM `product_props` WHERE a.product_id = product_id AND `pn_id` = 9 AND `pv_id` = 1 ) 
        AND EXISTS ( SELECT product_id FROM `product_props` WHERE a.product_id = product_id AND `pn_id` = 8 AND `pv_id` = 6 ) 
        );

耗时5.7-5.85 （执行10次的范围）

explain分析：

SQL 性能实战来了，机不可失！

SELECT SQL_NO_CACHE
    count(1) 
FROM
    pdi_product a
    join (SELECT DISTINCT
    `product_id` 
FROM
    `product_props` AS a 
WHERE
    a.`pn_id` = 5 
    AND a.`pv_id` = 127 
    AND EXISTS ( SELECT product_id FROM `product_props` WHERE a.product_id = product_id AND `pn_id` = 11 AND `pv_id` = 22 ) 
    AND EXISTS ( SELECT product_id FROM `product_props` WHERE a.product_id = product_id AND `pn_id` = 10 AND `pv_id` = 18 ) 
    AND EXISTS ( SELECT product_id FROM `product_props` WHERE a.product_id = product_id AND `pn_id` = 9 AND `pv_id` = 1 ) 
    AND EXISTS ( SELECT product_id FROM `product_props` WHERE a.product_id = product_id AND `pn_id` = 8 AND `pv_id` = 6 ) ) b
on a.product_id = b.product_id
WHERE
    a.STATUS = 1