รบกวนช่วยดูการรับค่าจากลิงค์ให้หน่อยครับ คือส่งมาแล้วแต่นำมา select ไม่ได้ครับ

                        <?php
			include("config.inc.php");
		 	$sql = "select * from product  order by PRODUCT_CODE  desc LIMIT 3 ";
			$result = mysql_query($sql);

	echo"<table align=left width=440>";
	echo"<tr bgcolor=#FFFFCC>";
	echo"<td align=\"center\"  width=\"130\">SAMPLE</td>";
	echo"<td align=\"center\" width=\"70\"><FONT FACE=\"Arial, Helvetica, sans-serif\" size=2>CODE</font></td>";
	echo"<td align=\"center\"  width=\"200\"><FONT FACE=\"Arial, Helvetica, sans-serif\" size=2>DETAIL</font></td>";
	echo"<td align=\"center\" width=\"70\"><FONT FACE=\"Arial, Helvetica, sans-serif\" size=2>PRICE</font></td>";
	echo"</tr>";
while ($arr = mysql_fetch_array($result)) {
	echo"<tr>";	
	echo "<td align=\"center\"><a href=Product_Detail.php?code=".  $arr["PRODUCT_CODE"]."><img src=\"Picture/".$arr["PRODUCT_SMALLPIC"]." \"  border=\"0\"/></a></td>";		
	echo"<td><FONT FACE=\"Arial, Helvetica, sans-serif\"  size=2 >".$arr["PRODUCT_CODE"]."</font></td>";																																							
	echo"<td><FONT FACE=\"Arial, Helvetica, sans-serif\"  size=2 >".$arr["PRODUCT_DETAIL"]."</font></td>";
	echo"<td align=\"left\"><FONT FACE=\"Arial, Helvetica, sans-serif\"  size=2 >".$arr["PRODUCT_PRICE"]."</font></td>";
    echo"</tr>";
}
	echo"</table>";
	
mysql_close();
?>

<?
          include("config.inc.php");
		 $product_id = $_POST['code'];
		
		 	$sql = "select * from product  Where PRODUCT_CODE = '$product_id' ";
			echo $sql;
			$result = mysql_query($sql);
			while ($row = mysql_fetch_array($result)) {
				$code 	 = $row["PRODUCT_CODE"];
  				$name = $row["PRODUCT_NAME"];
  				$detail = $row["PRODUCT_DETAIL"];
  				$size = $row["PRODUCT_SIZE"];
				$price = $row["PRODUCT_PRICE"];
				$material = $row["PRODUCT_MATERIAL"];
				$keyfeature = $row["PRODUCT_KEYFEATURE"];
				$goodtoknow = $row["PRODUCT_GOODTOKNOW"];
				$careinstruction = $row["PRODUCT_CAREINSTRUCTION"];
				$pic = $row["PRODUCT_BIGPIC"];
  			}
		  ?>