Ajax请求最大执行超时

Question

While using this code to gather data using an Ajax XHTMLRequest I'm getting an PHP Max execution timeout

if(isset($_GET['func']) and $_GET['func'] == 'feed') {
    global $ado;
    $old_msg_id = $_GET['old_msg_id']; 
    $result = $ado->exec("SELECT * FROM `earnings` ORDER BY `id` DESC LIMIT 1");
    while($row = $ado->fetch_assoc($result)) {
        $last_msg_id = $row['id']; 
    }
    while($last_msg_id <= $old_msg_id) {
        $result = $ado->exec("SELECT * FROM `earnings` ORDER BY `id` DESC LIMIT 1");
        while($row = $ado->fetch_assoc($result)) {
            $last_msg_id = $row['id'];
        }
    }
    $response = array();
    $response['msg'] = 'new';
    $response['old_msg_id'] = $last_msg_id;
    echo json_encode($response);
}

The error I'm receiving in the error_log is

PHP Fatal error:  Maximum execution time of 30 seconds exceeded in /ajax.php on line 165

Line 165 is the following :

while($last_msg_id <= $old_msg_id) {

I currently don't see a problem with the code, any hints as to what's wrong ?

Answer 1

JS level

In AJAX you can post the time out like below,

       jQuery.ajax({
           url: 'ajaxhandler.php',
           success: function (result) {                               
                returned_value=result;
           },
           timeout: 10000,
           async: false
        });

PHP level

If you are getting PHP you can change it in the PHP.ini

max_execution_time = 30 //make it like 300

Else in your PHP code use set_time_limit

When called, set_time_limit() restarts the timeout counter from zero. In other words, if the timeout is the default 30 seconds, and 25 seconds into script execution a call such as set_time_limit(20) is made, the script will run for a total of 45 seconds before timing out.

Also make sure that those while loops are not never ending loops.

Answer 2

看来您的两个while循环执行所需的时间太长，数据库中是否分配了数据。