php - Codeigniter:两表查询

Question

我有两个表要查询。一张表包含诊所的记录，另一张表包含实验室的记录。这会导致(消息:尝试获取非对象的属性)。我错过了什么？

我想查看临床表中但实验室表中没有的 PID。

我的 Controller :

function queries(){
    $data['results'] = $this->main_model->queries();
    $this->load->view('queries', $data);

}

我的模型:

function queries(){

    $this->db->select('*');
    $this->db->from('clinic');
    $this->db->where('participantID NOT IN (SELECT  participantID FROM lab)', NULL, FALSE);
    $results = $this->db->get();
    return $results;
}

最后说一下我的看法:

<?php 

foreach($results as $row){


echo " <tr > <td> $row->participantID </td>  <td> </td> <td> </td> <td> </td> <td> </td> <td> </td></tr>";


} 

?>

Answer 1

Controller :

function getall(){      
$this->load->model('result_model');
$data['query'] =$this->result_model->result_getall();
print_r($data['query']);
die();
$this->load->view('result_view', $data);
}

型号:

function result_getall(){

$this->db->select('*');
$this->db->from('tblanswers');
$this->db->join('credentials', 'tblanswers.answerid = credentials.cid', 'left'); 
$query = $this->db->get();
return $query->result();

}

查看:

 <?php foreach ($query as $row): ?>      

     <?php echo $row->answerA;?><br>

     <?php endforeach; ?>