MySQL的选择查询与PHP foreach [英] mysql select query with php foreach

问题描述

我正在尝试编写一个函数，该函数将从表中获取ID，然后希望将所有ID都包含在数组中，以便将这些ID用于另一个函数中进行处理. 我写了下面的内容，但它不是数组方法，而且它两次打印id.我在网上搜索，他们都建议使用mysql_fetch_assoc并删除每个..但就我而言，我正在使用zend适配器fetchAll来获取输出.请让我知道如何才能在数组中获取ID，并且也只能获取一次，以便我可以传递此数组，并且每个ID都会被一个一个地处理..现在，我拥有的只是在处理第一个ID之后才停止.谢谢.

I am trying to write a function where I will get the id's from a table and then I want to have the all the id's in the array so that these id's used in another function to be processed. I wrote the below but it's not array method and also it's printing the id's twice. I searched online and they all suggest to use mysql_fetch_assoc and remove for each..but in my case I am using the zend adapter fetchAll to get the output. Please let me know how I can get the id's in the array and also only once so that I can pass this array and each id is processed one by one..right now with what I have is just stopping after the first one is processed. Thanks.

function getID()
  {
    $sql = 'SELECT user_id FROM users WHERE ready = "1" ';
    $idList = $this->getAdapter()->fetchAll($sql);
    if(!empty($idList)) {
        foreach($idList as $value) {
            echo $value['user_id']."\n";
        }
    }
   }


Output 
201
223
231
334
201
223
231
334

推荐答案

尝试一下.

function getIDs() {
  $result = array();
  $sql = 'SELECT user_id FROM users WHERE ready = "1" ';
  $idList = $this->getAdapter()->fetchAll($sql);
  if(!empty($idList)) {
    foreach($idList as $value) {
      echo $value['user_id']."\n";
      array_push(result, $value['user_id']);
    }
  }
  // $result = array_unique($result);
  return $result;
}

然后您将通过以下方式获取数组:

You will then get the array by:

$bunch_of_ids = getIDs();

您应该弄清楚为什么要重复它们，但是如果不能，可以使用以下方法使数组内容唯一:

You should figure out why they are being duplicated, but in case you can't, you can make the array content unique with:

$result = array_unique($result);

将其放在函数内return $result;之前.我已经在上面的函数中对其进行了评论，因为最好找出为什么它首先要被复制.正如我在对您的问题的评论中指出的那样，请确保该函数没有被调用两次.还要检查数据库中是否有重复的条目(尽管如果'user_id'是主键，那应该是不可能的.)

Put that right before return $result; inside the function. I've commented it in the function above because would be much better to find out why it's being duplicated in the first place. As I noted in a comment to your question, please make sure that the function isn't being called twice. Also check the database for duplicate entries (although that shouldn't be possible if 'user_id' is a primary key).

(还请注意，我将函数重命名为getIDs()，因为让getID()函数返回多个值是没有意义的.:))

(Please also note that I renamed the function to getIDs() because it makes no sense to have a getID() function returning multiple values. :) )

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