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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：
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：
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
耗时5.7-6.0（执行10次的范围）
- explain分析：
可以看到如果单纯查属性表，第一位的速度是最快的，可要查产品状态后，速度反而不如子查询。
经explain分析，第一个子查询速度之所以快是因为它的sql简单，select_type皆为simple。
而不管是join还是exists的方式，select_type大多为DERIVED，DEPENDENT SUBQUERY。
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