function my_shortcode( $attr, $content )
{
    $clean = copter_remove_crappy_markup($content);
    return '<div class="my_shortcode">' . $clean . '</div>';
}
add_shortcode('recommend', 'recommend_table');
function recommend_table($atts=array()){
   global $wpdb;
   
   $results = $wpdb->get_results("SELECT *FROM recommend");
   // $wpdb->get_results()를 사용하면 DB에서 여러줄 데이터를 가져올 수 있습니다.
   ?>
   <table>
   <style>
   table {
    
     border-top: 1px solid #dddddd;
     
   }

      th {
    text-align: center;
    color: #111111;
    border-right: 1px solid #ccc;
    border-bottom: 1px solid #ccc;

  }
  td {
    text-align: center;
    border-right: 1px solid #ccc;
    border-bottom: 1px solid #ccc;
  }
    </style>
   <tr>
      
      <th>종목명</th>
      <th>매수일</th>
      <th>매수가</th>
      <th>목표가</th>
      <th>손절가</th>
      <th>최종보유일</th>
   </tr>

   <?php foreach($results as $item):?>
   <tr>
      
      <th><?php echo $item->dbdb?></th>
      <th><?php echo $item->dbdbd?></th>
      <th><?php echo $item->dbdbdb?></th>
      <th><?php echo $item->dbdbdbdbdbd?></th>
      <th><?php echo $item->dbdbdbdbd?></th>
      <th><?php echo $item->dbdbdbdbdbd?></th>
   </tr>
   <?php endforeach?>
   </table>
   <?php
   return ob_get_clean();
   
}

https://imgur.com/a/aCi7TlX 숏코드를 입력하여 사용하였는데 이처럼 출력이 됩니다.

코드의 어느부분이 잘못되어서 에러가 나는 걸까요?