ผมต้องการเขียนโปรแกรมให้เชคค่าที่ได้รับมาว่าตรงกับในdatabse ที่มีไหมถ้าไม่มีให้ขึ้นเป็นแจ้งเตือนขึ้นมา ขอแนวทางทีครับ !!

<script language="JavaScript">
    	function ClickCheckAll(vol)
    	{

    		var i=1;
    		for(i=1;i<=document.frmMain.hdnCount.value;i++)
    		{
    			if(vol.checked == true)
    			{
    				eval("document.frmMain.chkDel"+i+".checked=true");
    			}
    			else
    			{
    				eval("document.frmMain.chkDel"+i+".checked=false");
    			}
    		}
    	}

      function onDelete()
      {
          if(confirm('Do you want to delete ?')==true)
            {
            return true;
            }

            else

            {
            return false;
            }
        }
</script>

<?php include("header.php"); ?>
<!-- Page Content -->
<div class="container">

<!-- Page Heading/Breadcrumbs -->
<div class="row">
    <div class="col-lg-12">
<center>
        <h3 class="page-header ">สแกนรายชื่อรถเข้าสาย</h3>
    </center>
    <?php
        date_default_timezone_set('Asia/Bangkok');
    ?>



        <!-- ///////////////////////////////สแกนบัตร /////////////////////////////////////////-->
          <form class="container w3-card-4 "  action="ScannerSave.php" name="scansave" method="post"  enctype="multipart/form-data">
            <br>

                 <p>
                       <label class="w3-text-blue"  ><b>สายรถ</b></label>
                       <input class="form-control" name="txtNamecar" type="text" placeholder="สายรถ"></p>
                 <p>
                    <label class="w3-text-blue"  ><b>สแกนบัตร</b></label>
                    <input class="form-control" name="txtBadgeID" type="text" placeholder="สแกนบัตร"></p>

                <p>
                    <label class="w3-text-blue"  ><b>เวลา</b></label>
                    <input class="form-control" name="txttime" type="text"
                    placeholder="เวลา" value="<?php echo date("m-d-Y H:i:s") ?>"></p>

          <p>
              <button class="w3-btn w3-blue w3-round-large" style="width:20%" type="add" name="add" value="add" >ADD</button>
          </p>

          </form>
          <br>
              <!-- ///////////////////////////////สแกนบัตร /////////////////////////////////////////-->

              <!-- ///////////////////////////////เพิ่มชื่อใหม่ /////////////////////////////////////////-->
            <form class="container w3-card-4 "  action="AddNameEmployee.php" name="scannameemply" method="post"  enctype="multipart/form-data">

          <br>
             <p>
           <label class="w3-text-blue"  ><b>BadgeID(กรณีไม่มีชื่อในข้อมูล)</b></label>
           <input class="form-control" name="txtBadgeID2" type="text" placeholder="Encode"></p>

              <p>
            <label class="w3-text-blue"  ><b>Encode(กรณีไม่มีชื่อในข้อมูล)</b></label>
            <input class="form-control" name="txtEncode" type="text" placeholder="Encode"></p>

            <p>
            <label class="w3-text-blue"  ><b>Name(กรณีไม่มีชื่อในข้อมูล)</b></label>
            <input class="form-control" name="txtName" type="text"  placeholder="Name"></p>

            <p>
                <button class="w3-btn w3-blue w3-round-large" style="width:20%" type="add" name="add" value="add" >ADD</button>
            </p>
            </form>

            <br>
                  <!-- ///////////////////////////////เพิ่มชื่อใหม่ /////////////////////////////////////////-->

                  <!-- ///////////////////////////////export ข้อมูล /////////////////////////////////////////-->
              <form class="container w3-card-4 "  action="scannerExport.php" name="scanexport" method="post"  enctype="multipart/form-data">
                <br>
                    <p>
                            <label class="w3-text-blue"  ><b>ตั้งชื่อไฟล์</b></label>
                            <input class="form-control" name="txtNamefile" type="text"  placeholder="ตั้งชื่อไฟล์"></p>

                    <p>
                            <button class="w3-btn w3-blue w3-round-large" style="width:20%" type="add" name="add" value="add" >Export</button>
                    </p>

              </form>
                <br>
                <!-- ///////////////////////////////export ข้อมูล /////////////////////////////////////////-->

        <?php

        $sql = "SELECT tbl_employeename.Employee_ID ,tbl_employeename.Employee_Name
        , tbl_badgeid.time ,tbl_badgeid.BadgeID , tbl_badgeid.Nlinecar , tbl_employeename.BadgeID
            FROM tbl_employeename
            LEFT JOIN tbl_badgeid ON (tbl_employeename.BadgeID=tbl_badgeid.BadgeID)
            WHERE tbl_badgeid.BadgeID  ";

            $query = mysqli_query($conn,$sql) or die(mysqli_error($conn)) ;

            while($result2=mysqli_fetch_array($query,MYSQLI_ASSOC))
            {
          $sd =    $result2["Employee_Name"];

            }
            echo $sd;


            $num_rows = mysqli_num_rows($query);

              $per_page = 30;   // Per Page
              $page  = 1;

              if(isset($_GET["Page"]))
              {
                $page = $_GET["Page"];
              }

              $prev_page = $page-1;
              $next_page = $page+1;

              $row_start = (($per_page*$page)-$per_page);
              if($num_rows<=$per_page)
              {
                $num_pages =1;
              }
              else if(($num_rows % $per_page)==0)
              {
                $num_pages =($num_rows/$per_page) ;
              }
              else
              {
                $num_pages =($num_rows/$per_page)+1;
                $num_pages = (int)$num_pages;
              }
              $row_end = $per_page * $page;
              if($row_end > $num_rows)
              {
                $row_end = $num_rows;
              }

              $sql .= " ORDER BY tbl_badgeid.BadgeID ASC  LIMIT $row_start ,$row_end ";
           $query = mysqli_query($conn,$sql) or die(mysqli_error($conn)) ;

         ?>

         <form name="frmMain" action="DeleteAllscanner.php" method="post" >
         <center>
               <input type="hidden" name="hdnCmd" value="">
               <div class="container"  style="margin-top:1%" >
                 <div class="row">

              <table  class="table table-hover table-striped w3-card-4 table-bordered table-condensed" >
              <thead>
              <tr class="color"  >
                <!--ลิ้ง -->

                 <th > <div align="center">ENcode </div></th>
                 <th > <div align="center">Name </div></th>
                 <th > <div align="center">time </div></th>
                 <th > <div align="center">Namelinecar </div></th>
                 <th > <div align="center">Delete </div></th>
              </tr>
              </thead>
                </div>
                 </div>
                   </div>

             <?php

             $i = 0;
             while($result=mysqli_fetch_array($query,MYSQLI_ASSOC))
             {
               $i++;

             ?>

               <tr class="thaifont">

                 <td id='name' ><div align="center"><?php echo $result["Employee_ID"];?></div></td>
                 <td><div align="center"><?php echo $result["Employee_Name"];?></div></td>
                 <td><div align="center"><?php echo $result["time"];?></div></td>
                 <td><div align="center"><?php echo $result["Nlinecar"];?></div></td>

                 <td align="center"><a id="delete<?php echo $i;?>" class="various iframe"
                   href="JavaScript:if(confirm('Confirm Delete?') == true){window.location='deletefrom-scanner.php?BadgeID=<?php echo $result["BadgeID"];?>';}">Delete</a></td>
               </tr>

             <?php
             }
             ?>

             </table>
             <div class="col-md-12">
         				<button class="w3-btn w3-blue w3-round-large" type="btnDeleteAll" name="btnDeleteAll" value="DeleteAll"
         				 style="width: 27%"  >DeleteAll</button>
             </div >

         			</center>
                </form>


         <center>
         Total <?php echo $num_rows;?> Record : <?php echo $num_pages;?> Page :
         <?php
         if($prev_page)
         {
         echo " <a href='$_SERVER[SCRIPT_NAME]?Page=$prev_page&txtKeyword=$strKeyword'><< Back</a> ";
         }

         for($i=1; $i<=$num_pages; $i++){
         if($i != $page)
         {
         echo "[ <a href='$_SERVER[SCRIPT_NAME]?Page=$i&txtKeyword=$strKeyword'>$i</a> ]";
         }
         else
         {
         echo "<b> $i </b>";
         }
         }
         if($page!=$num_pages)
         {
         echo " <a href ='$_SERVER[SCRIPT_NAME]?Page=$next_page&txtKeyword=$strKeyword'>Next>></a> ";
         }
         $conn = null;
         ?>
         </center>

<!-- From-->
  </div>
<!-- From-->
<!-- /.row -->
</div>
<!-- /.container -->
</div>

<?php include("footer.php"); ?>