ช่วยแนะนำผมเรื่องการดึงfiled ชนิด time จาก mysql ไป plot ในแนวแกน x ทีครับ

//query 
$SQL = mysql_query("SELECT time1 AS T,Snrd,Snru FROM Data Where date1='2011-07-22'ORDER BY T");

while($row = mysql_fetch_assoc($SQL)){

 $snrd[] = array( $row['T'], $row['Snrd'] );
 $snru[] = array( $row['T'], $row['Snru'] );
 $T[] = array($row['T'], $row['T']);
 
}


<!--     HTML     -->
<h1>TOT</h1>
<div id="placeholder" style="width:600px;height:300px;"></div>

<script id="source" language="javascript" type="text/javascript">
$(function () {

 var d1 = <?php echo json_encode($snrd).';'; ?>
 var d2 = <?php echo json_encode($snru).';'; ?>
 $.plot($("#placeholder"), [
 { label: "snrd",  data: d1},{ label: "snru",  data: d2}
 ],
 {shadowSize: 0,
 series: {
 lines: { show: true,fill: true,lineWidth: 3 },
 },
 xaxis: {
 ticks: <?php echo json_encode($T); ?>
 }
 });
});
</script>