PHP类如何与MySQL数据库交互?

The other day, while developing my PHP project and implementing the User class, i started to wonder how this class should interact with the MySQL database the project is using.

前几天，在开发我的PHP项目和实现User类的同时，我开始思考这个类如何与项目使用的MySQL数据库交互。

Let me start with an example: let's say I have a getName() method, inside the User class, that returns the user's real name. What's the more fitting way to implement that method?

让我从一个例子开始:假设我在User类中有一个getName()方法，它返回用户的真实姓名。实现这种方法的更合适的方法是什么?

I came up with 2 solutions:

我想出了两个解决方案:

I put the DB query inside the getName() and only get what I need like this:

我将DB查询放入getName()中，只得到我需要的东西:
```
public function getName() {

    // MySQL query code here
}
```
I create a load() method inside the User class that load all the user data inside the class structure and then the getName() is something like this:

我在User类中创建了load()方法，它在类结构中加载所有用户数据，然后getName()是这样的:
```
private $name;

// Load all user data inside the class' structure
public function load() {

    $this->name = // MySQL query here
}

public function getName() {

    return $this->name;
}
```

I thought, not sure if mistakenly or not, that the first way is more efficient because i only get the data I need, while the second way is more OOP but less efficient.

我认为，不确定是否错误，第一种方法更有效，因为我只得到我需要的数据，而第二种方法是更多的OOP，但效率较低。

So, here's the question: what is the better way? Why? Are there better ways?

所以，问题是:什么是更好的方法?为什么?有更好的方法吗?

3 个解决方案

#1

Either way, consider storing/caching the results of that so you do not make a query every time you use getName on that object. Also, consider not wrrying about all that by using a ORM/DBAL Solution like propel or doctrine.

无论哪种方式，都可以考虑存储/缓存结果，所以每次在该对象上使用getName时，都不会生成查询。另外，考虑使用像推进或教义这样的ORM/DBAL解决方案来解决所有问题。

Also check out Lazy Loading and the Active Record Pattern

还可以检查延迟加载和活动记录模式。

#2

Run your query just in time and only run it once (unless you know the value might change), try something like the following:

及时运行您的查询，并且只运行一次(除非您知道值可能会发生变化)，尝试如下操作:

 class User {
   protected $data;

   function getName()
   {
     if (!isset($data['name'])) {
       // if you can load more than just $this->data['name'] in one query
       // you probably should.
       $this->data['name'] = // query here
     }
     return $this->data['name'];
   }

 }

#3

Aside from the question being kinda broad (as there are countless patterns), the second way you mentioned is better IMO, and to add to it I would also suggest supplying ID as a parameter which you could then use to build a single query to fetch the user by ID and then manually assign all properties (from the fetched row).

除了有点宽泛的问题(如有无数的模式),你提到的第二种方式是更好的国际海事组织,并添加我也建议提供ID作为参数,你可以用来建立一个查询来获取用户的ID,然后手动分配所有属性(从所获取的行)。

#1