如何在php中检查字符串形式的数据库值

这是我的密码

    <?php
$SupportingMaterialTaskSql = "select task_name,section_name,ref_student_id from scores where ref_student_id = '".$studentid."' and section_name = 'sm1' GROUP BY task_name ORDER BY cast( SUBSTRING( task_name, 5, 2 ) AS unsigned ) ASC";

            $SupportingMaterialTaskResults = $obj->selectQuery($SupportingMaterialTaskSql);

            if($SupportingMaterialTaskResults > 0)
            {
                foreach($SupportingMaterialTaskResults as $Key => $SupportingMaterialTaskRow)
                {
                    $Task = $SupportingMaterialTaskRow['task_name'];

                    $str = "Task";
                    $TaskName = str_replace($str, "Task ", $Task);
?>
                <tr>
                  <td width="30%"  class="f13_blue cellbg"><?php echo $TaskName; ?></td>
                </tr> 
                <?php 
                } 

            } 
            ?>

所以我只想得到这样的结果。。如果数据库具有类似Task1的值，则打印Task1，否则打印Task1不适用

---

那么，我该如何解决这个问题呢？

类似于以下的方法可能会奏效：

<?php

function check_not_null($var){
  if(trim($var) == ""){
    $var = "N/A";
  }
  return($var);
}


// some query info here...


while($fetch = mysqli_fetch_array($query)) {
  $task1 = check_not_null($fetch['task1']);
  $task2 = check_not_null($fetch['task2']);
  $task3 = check_not_null($fetch['task3']);
  // now echo or use the vars.. each loop they will be rechecked..
}

?>

---

是任务值，表列？任务名称部分任务名称参考学生id任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1任务sm1是这是任务名称字段值。

<?php

function check_not_null($var){
  if(trim($var) == ""){
    $var = "N/A";
  }
  return($var);
}


// some query info here...


while($fetch = mysqli_fetch_array($query)) {
  $task1 = check_not_null($fetch['task1']);
  $task2 = check_not_null($fetch['task2']);
  $task3 = check_not_null($fetch['task3']);
  // now echo or use the vars.. each loop they will be rechecked..
}

?>