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HomeBackend DevelopmentPHP Tutorialmysql - PHP 处理 数据库多表,既能高效又能思路清晰如何处理的?

【情况如下】
在表1中 记录着
自行车编号 租户商家

<code>1           a     
2           a
3           b
4           c
</code>

[这里的意思是,不同的商家。拥有的自行车,商家拥有自行车表]

表2
自行车编号 租出时间 租出金额

<code>1           2         4
1           3         5
1           6         10
2           3         5
3           4         7
</code>

[这里 意味着。不同的商家 对自己的自行车 租出时间不同设置的价格,自行车价格表]

表3
自行车编号 租出时间 租的人

<code>1          2        用户1
1          3        用户2
2          4        用户3
3          2        用户4
4          1        用户5

[这里指,用户,在今天使用的自行车和租的时间,租车记录]


</code>

【那么问题来了】
我现在想知道

1、商家今天租车,同1车,租车总次数
最后要拿到
自行车编号 租出2小时几次? 租出3小时多少次?租出4小时多少次?

我有2种方法。第一种是用 程序 先查出所有车的租出记录。然后在用程序来统计分别租出去那种时间,和多少次。
请问这种类型的数据统计。PHP一般是怎么来达到既能考虑到效率。又能很简洁!

回复内容:

【情况如下】
在表1中 记录着
自行车编号 租户商家

<code>1           a     
2           a
3           b
4           c
</code>

[这里的意思是,不同的商家。拥有的自行车,商家拥有自行车表]

表2
自行车编号 租出时间 租出金额

<code>1           2         4
1           3         5
1           6         10
2           3         5
3           4         7
</code>

[这里 意味着。不同的商家 对自己的自行车 租出时间不同设置的价格,自行车价格表]

表3
自行车编号 租出时间 租的人

<code>1          2        用户1
1          3        用户2
2          4        用户3
3          2        用户4
4          1        用户5

[这里指,用户,在今天使用的自行车和租的时间,租车记录]


</code>

【那么问题来了】
我现在想知道

1、商家今天租车,同1车,租车总次数
最后要拿到
自行车编号 租出2小时几次? 租出3小时多少次?租出4小时多少次?

我有2种方法。第一种是用 程序 先查出所有车的租出记录。然后在用程序来统计分别租出去那种时间,和多少次。
请问这种类型的数据统计。PHP一般是怎么来达到既能考虑到效率。又能很简洁!

这个直接就可以用sql语句来解决,用左连接可以查出任何你想要的数据,如果用php处理的话,一次性把所有的数据都取出来,然后再处理也是可以的,千万不要循环中再去查询数据库。

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