如何在Zend DB模型中使用'distinct' [英] How to use 'distinct' in zend db model

问题描述

我已经搜索了很长时间才能使该功能正常工作.

I have search for a long time to get this thing work.

我想要知道的是如何在zend db模型中使用'distinct'，以使我对用户关注者的选择唯一.

What I want is to know how I user the 'distinct' in a zend db model to make my selection for the followers of a user unique.

我的数据库模型为用户计算关注者(这里我需要添加'distinct')

My db model to count followers for a user (here I need to add the 'distinct')

public function countFollowers($user_id) 
{    
    $rowset       = $this->fetchAll("user_id = $user_id");
    $rowCount     = count($rowset);

    if ($rowCount > 0) {
      return $rowCount;
    } else {
      return $rowCount;
    }
}

此函数是'扩展Application_Model_DbTable_Followers类Zend_Db_Table_Abstract'的一部分

This function is part of 'class Application_Model_DbTable_Followers extends Zend_Db_Table_Abstract'

我的表结构

• id
• article_id//由"user_id"撰写的文章的ID.
• user_id//文章的user_id所有者
• follower_id//已关注此文章的成员
• date//跟踪日期

'user_id'可以写成各种文章，关注者可以关注同一位作家的各种文章.我想增加一个唯一的关注者人数.例如，我想要的是，如果关注者关注一位作者的8篇文章，则必须将其与计数中的"1"进行比较.

'user_id' can be written various articles, the follower can follow various articles of the same writer. I want to make a unique follower count. As an example what I want, If a follower is following 8 articles of one writer it has to be compared to '1' in the count.

我希望这一点足够清楚，以了解我想要达到的目标.

I hope this will be clear enough to understand what I tried to reach.

以诚挚的问候，

Nicky

推荐答案

使用与众不同的方法:

public function countFollowers($user_id) 
{
    $select = $this->select()
              ->distinct()
              ->where('user_id = ?', $user_id);

    $rowset = $this->fetchAll($select);
    $rowCount = count($rowset);

    return $rowCount;
}

在进行有问题的编辑后，获得用户的关注者数量.您实际上需要使用 group 不区分大小写.我已经测试了以下查询的工作原理，以获取要进行count()处理的数据，

After edit in question to get count of followers of a user. You actually need to use group NOT distinct. I have tested the following query works to fetch the data to be count()ed,

SELECT * FROM followers其中user_id = 1 GROUP BY user_id， follower_id

SELECT * FROM followers WHERE user_id = 1 GROUP BY user_id, follower_id

我还没有测试代码，但是类似的东西应该可以工作:

I have not tested the code, but something like this should work:

public function countFollowers($user_id) 
{
    $select = $this->select()
              ->where('user_id = ?', $user_id)
              ->group(array('user_id', 'follower_id')); 

    $rowset = $this->fetchAll($select);
    $rowCount = count($rowset);

    return $rowCount;
}

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