#วิธีการตรวจสอบ check query error mysqli การ debug PHP ง่ายๆ

<?php 

  echo $_POST['std_id'];

    echo $_GET['Action'];

?>

<?php

   if($_GET['Action']=="INSERT'){

          $sql="INSERT  INTO  student set std_id='".$std_id."',card_id='".$card_id."',gender='".$gender."',full_name='".$full_name."',class='".$class."',Email='".$Email."',birthdate='".$birthdate."',timein='".$timein."',std_pic='".$std_pic."',std_file='".$std_file."',cn_id='".$cn_id."',subject1='".$subject1."',subject2='".$subject2."',subject3='".$subject3."',subject4='".$subject4."',remark='".$remark."'";

          echo $sql;

          mysqli_query($conn,$sql);

   }

?>

INSERT INTO student set std_id='1111',card_id='1111111111111',gender='1',full_name='สมชาย ใจไม่ด้านพอ',class='4',Email='nay-banana@hotmail.com',birthdate='2019-07-24',timein='10:50:36',std_pic='',std_file='',cn_id='10',subject1='checked',subject2='',subject3='checked',subject4='',remark='0141'