Php 活动记录方法选择

我尝试在users类中模拟活动记录模式。 在考试中显示下面的代码

Codice PHP:
//method
    public function getUtenti($criteria = NULL ,$value = NULL){ 
        $sql ="SELECT * FROM utenti "; 
        $sql.="LEFT JOIN tecnici ON tec_idtecnico = idutente "; 
        if($criteria != "") 
            $sql.="WHERE ".$criteria; 
        return $this->db->fetchAll($sql,$value); 
    } 

//metodo db 
    public function fetchAll($sql, array $params = array()){  
        return $this->executeQuery($sql, $params)->fetchAll(PDO::FETCH_ASSOC);  
    }  

//method for get users 

foreach($user->getUtenti('flagamm = :flagamm', array('flagamm' => 'x')) as $rk){ 
   echo "<option value=\"".$rk['idutente']."\">".$rk['tec_ragionesociale']."</option>"; 
                                                } 

但是如何构建GetUser（）方法呢？ 我可以通过GetUsers（）方法实现这一点

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但是我不能决定比较运算符=，！=，ecc

您说问题在于如何从$\u POST变量构建查询。你能展示一下你在这方面的尝试吗？也许我们能看出你的错误所在。我已经编辑了主要帖子，对吗？

$user = new user(); 
$user->setCompany($_POST['company']);//set the property , in this method i control the leng, make trim ecc ecc. 
$set->GetUser(); //this method should give me back all users filters with company 

$sql = "SELECT * Users ";
if($this->company != "") 
   $sql.="WHERE company = ".$this->company;