mysql – 是否有可能更快地获得查询？

我是sql的新手,需要帮助我有4个表：

helmet                                  arm
+------+---------+-----+--------+       +------+---------+-----+--------+
|  id  |   name  | def | weight |       |  id  |   name  | def | weight |
+------+---------+-----+--------+       +------+---------+-----+--------+
|   1  |  head1  |  5  |   2.2  |       |   1  |   arm1  |  4  |   2.7  |
|   2  |  head2  |  6  |   2.9  |       |   2  |   arm2  |  5  |   3.1  |
|   3  |  head3  |  7  |   3.5  |       |   3  |   arm3  |  2  |   1.8  |
+------+---------+-----+--------+       +------+---------+-----+--------+

body                                    leg
+------+---------+-----+--------+       +------+---------+-----+--------+
|  id  |   name  | def | weight |       |  id  |   name  | def | weight |
+------+---------+-----+--------+       +------+---------+-----+--------+
|   1  |  body1  |  10  |  5.5  |       |   1  |   leg1  |  8  |   3.5  |
|   2  |  body2  |  5   |  2.4  |       |   2  |   leg2  |  5  |   2.0  |
|   3  |  body3  |  17  |  6.9  |       |   3  |   leg3  |  8  |   1.8  |
+------+---------+-----+--------+       +------+---------+-----+--------+`

我正在寻找总重量< =输入的最高总保额
像这样：总重量< = 10 查询：

select 
    helmet.name as hname, body.name as bname, 
    arm.name as aname, leg.name as lname,
    helmet.poise + body.poise + arm.poise + leg.poise as totalpoise, 
    helmet.weight + body.weight + arm.weight + leg.weight as totalweight 
from 
    helmet 
inner join 
    body on 1=1
inner join 
    arm on 1=1
inner join 
    leg on 1=1 
where 
    helmet.weight + body.weight + arm.weight + leg.weight <= 10
order by 
    totalpoise desc 
limit 5

结果：

+-------+-------+-------+-------+----------+-------------+
| hname | bname | aname | lname | totaldef | totalweight |
+-------+-------+------ +-------+----------+-------------+
| head2 | body2 |  arm1 |  leg3 |    23    |     9.8     |
| head1 | body2 |  arm2 |  leg3 |    23    |     9.5     |
| head3 | body2 |  arm3 |  leg3 |    22    |     9.5     |
| head1 | body2 |  arm1 |  leg3 |    22    |     9.1     |
| head2 | body2 |  arm3 |  leg3 |    21    |     8.9     |
+-------+-------+-------+-------+----------+-------------+

问题是每个表有大约100行,因此可能的结果是100米行.查询需要很长时间.我不确定这是关于我的硬件或数据库或查询的类型.

P.S：我使用HDD并且有8GB的内存.我曾在MysqL和Postgresql上测试过.

更新
我还没有创建索引.

这是解释计划吗？
explain plan

多久时间？
这取决于输入.
在MysqL上,它只需几分钟 – 几个小时.
在Postgresql上大约需要30秒–2分钟.

更新2我的表永远不会改变.那么我可以将所有结果存储在一个表中吗？有帮助吗？

更新3我想到分区.它可能要快得多,但问题是如果下部分区中的某些[装甲设置]在上部分区中的totaldef超过[armor set].
例：

[head1,arm1,body1,leg1][totaldef 25][totalweight 9.9]
[head2,arm2,body2,leg2][totaldef 20][totalweight 11.0]

所以分区总重量> 10会错过[盔甲套装]因为它在其他分区中.

这是任何想要测试的人的CSV文件. CSV file

更新4我认为最快的方法是创建materialized view,但我认为性能的关键是排序.我不知道哪种类型可以帮助物化视图或索引,但我对它们进行了排序,这很有帮助.

我没想到会得到很多像这样的帮助.谢谢.

解决方法:

具有适当索引的materialized view表现相当不错,在我老化的SSD桌面上使用Postgresql配置库存1.8秒：

create materialized view v as
select
    h.name as hname, b.name as bname, a.name as aname, l.name as lname,
    total_poise, total_weight
from
    helmet h
    cross join
    body b
    cross join
    arm a
    cross join
    leg l
    cross join lateral (
        select
            h.weight + b.weight + l.weight + a.weight as total_weight,
            h.poise + b.poise + l.poise + a.poise as total_poise
    ) total
order by total_poise desc, total_weight
;

create index v_index on v (total_poise desc, total_weight);

执行和分析：

select *
from v
where total_weight <= 10
order by total_poise desc, total_weight
limit 5
;
         hname         |          bname           |         aname          |          lname           | total_poise | total_weight 
-----------------------+--------------------------+------------------------+--------------------------+-------------+--------------
 Fume Sorcerer Mask+10 | Moon Butterfly Wings+5   | Velstadt`s Gauntlets+5 | Prisoner`s Waistcloth+10 |          20 |          9.4
 Fume Sorcerer Mask+10 | Lion Warrior Cape+10     | Velstadt`s Gauntlets+5 | Prisoner`s Waistcloth+10 |          20 |          9.5
 Fume Sorcerer Mask+10 | Red Lion Warrior Cape+10 | Velstadt`s Gauntlets+5 | Prisoner`s Waistcloth+10 |          20 |          9.5
 Fume Sorcerer Mask+10 | Moon Butterfly Wings+5   | Velstadt`s Gauntlets+5 | Lion Warrior Skirt+10    |          20 |          9.6
 Fume Sorcerer Mask+10 | Moon Butterfly Wings+5   | Velstadt`s Gauntlets+5 | Moon Butterfly Skirt+10  |          20 |          9.6


explain analyze
select *
from v
where total_weight <= 10
order by total_poise desc, total_weight
limit 5
;
                                                             QUERY PLAN                                                              
-------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=0.57..11.71 rows=5 width=88) (actual time=1847.680..1847.694 rows=5 loops=1)
   ->  Index Scan using v_index on v  (cost=0.57..11191615.70 rows=5020071 width=88) (actual time=1847.678..1847.691 rows=5 loops=1)
         Index Cond: (total_weight <= '10'::double precision)
 Planning time: 0.126 ms
 Execution time: 1847.722 ms

mysql – 是否有可能更快地获得查询？

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