อยากเพิ่มเงื่อนไขให้มัน show graph ตรง Final Test 2 ครับ

<form name="form1" method="GET"action="view_graph_spc.php"enctype="multipart/form-data">
      <table width="686" border="0" cellpadding="2">
      <tr>
        <td height="5" colspan="7"></td>
        </tr>
<td>
<font size="2" color="#6600ff">View Data SPC Control Chart from</font>

		 <input  type="text"name="dateStart"id="dateStart" size="8"value="<?=$_GET["dateStart"];?>"> 
<a href="javascript:displayDatePicker('dateStart')">
<img border="0" src="admin/image/icon/formcal.gif" width="15" height="18"></a>&nbsp;To

		 <input  type="text"name="dateStop" Id="dateStop"size="8"value="<?=$_GET["dateStop"];?>"> 
<a href="javascript:displayDatePicker('dateStop')">
<img border="0" src="admin/image/icon/formcal.gif" width="15" height="18"></a>
&nbsp;&nbsp;
<select name="Station"id="Station"value="<?=$GET["Station"];?>">
          <option value="Select Station." selected>Select Station.</option>
          <option value="Final Test 1.">Final Test 1.</option>
		  <option value="Final Test 2.">Final Test 2.</option>
        </select>
<input type="submit" value="View Graph">
</td>

<?php
include ("admin/jpgraph/src/jpgraph.php");
include ("admin/jpgraph/src/jpgraph_line.php");
include ('admin/module/connect.php');
//$strSQL = "SELECT * FROM tbl_spc";

if($_GET["dateStart"] and $_GET["dateStop"]!= ""){
	$strSQL = "SELECT * FROM tbl_spc WHERE Date BETWEEN '".$_GET["dateStart"]."' AND '".$_GET["dateStop"]."'";
	
} else
$strSQL = "SELECT * FROM tbl_spc";

$objQuery = mysql_query($strSQL) or die ("Error Query [".$strSQL."]");

// เตรียมข้อมุลที่จะแสดง เพื่อสร้างกราฟ
$datay=array();
while($objResult = mysql_fetch_array($objQuery))
{

$datay1[]= $objResult["Tilt"]; 
$datay2[]= $objResult["AvgG"]; 
$datay3[]= $objResult["Flatness"]; 
$datay4[]= $objResult["Noise"]; 
$datay5[]= $objResult["Date"]; 
}