php jquery Ajax 提交、读取 json

<mce:script type="text/javascript" language="javascript"><!--
function del(com_id,meet_id){
$.ajax({
url:'../company/meet.Ajax.php',
type:'POST',
data:{com_id:com_id,meet_id:meet_id},
dataType:"json",
timeout: 1000,
error: function(){
alert('Sorry, the server is busy now, please try again later.');
},
success: function(data){
if(data){
$("#row_"+data.meet_id).remove();
if($("#meeting_info").find("tr").length==1){
var tds = $("#meeting_info>tbody>tr:last").find("td").length;
$("#meeting_info>tbody").append('<tr id ="no_meet" <?=linecolor_v2(1)?> height="22" align="left"><td colspan="'+tds+'"><b>there is no meet now.</b></td></tr>');
}
} else {
alert("sorry, delete fail, please try again later.");
}
}
});
}
if($("#meeting_info").find("tr").length==1){
var tds = $("#meeting_info>tbody>tr:last").find("td").length;
$("#meeting_info>tbody").append('<tr id ="no_meet" <?=linecolor_v2(1)?> height="22" align="left"><td colspan="'+tds+'"><b>there is no meet now.</b></td></tr>');
}
// --></mce:script>
<?
$retval = '{"status":"fail"}';
if($_REQUEST['meet_id'] && $_REQUEST['com_id']) {
include_once("../include/function.php");
include_once("../include/dbconnect.php");
global $connectionid,$SITE_PARAS, $AGENT_INFO;
//data:{com_id:com_id,meet_id:meet_id}
$sql = "DELETE from RDL.MEETING WHERE MEET_PID = TO_NUMBER('".$_REQUEST['meet_id']."') AND COM_PID = TO_NUMBER('".$_REQUEST['com_id']."')";
$result = sql_exec($connectionid, $sql, false);
//print