Javascript 实时数据图表不工作

大家好，我正在制作实时java脚本图表，以显示数据库中的数据，但我得到的是什么都没有，它没有从数据库中捕获数据

我使用了这个php代码

   <?php

    header("Content-type: text/json");
   $servername = "localhost"; 
   $username = "root";  
   $password = "";
   $value = $_GET['value'];
   $date = time() * 1000;
   $ret = array($date, $value);
   echo json_encode($ret);
   $conn = mysql_connect($servername, $username, $password);
 if ($conn) {
 echo "Connected successfully";
} 
else {
 echo "connection failed";
} 
$conndb = mysql_select_db('database', $conn);
echo  "<br>";
$sql_insert ="insert into pulsesensor(value) values ('$value')";
if($sql_insert){
echo "insert successfull";
}
else {
echo "insert failed";
  }   echo  "<br>";
    $result = mysql_query($sql_insert);
     if($result){
         echo "insert successfull";
         }
         else {
         echo "insert failed" . mysql_error($result);
         }
        ?>

---

你的
mysql0.php
是什么？如果打开“开发人员工具”并查看“网络”选项卡，脚本是否发送请求？它有什么回报吗？它返回的数据是什么样子的？您的控制台中有错误吗？@Dimi my mysql0.php是我向服务器发送数据的php代码，数据正确发送并插入到数据库中，但我不知道是否正确返回，我有一个网站将数据库值显示为表，这也是idk为什么java脚本看不到服务器输出的数据值。
    <script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
    <script src="https://code.highcharts.com/highcharts.js"></script>
    <script src="https://code.highcharts.com/modules/exporting.js"></script>


    <div id="container" style="min-width: 310px; height: 400px; margin: 0 
     auto">
     </div>

/**
* Request data from the server, add it to the graph and set a timeout 
* to request again
*/
function requestData() {
   $.ajax({
    url: 'mysql0.php',
    success: function(point) {
        var series = chart.series[0],
            shift = series.data.length > 20; // shift if the series is 
                                             // longer than 20
        // add the point
        chart.series[0].addPoint(point, true, shift);

        // call it again after one second
        setTimeout(requestData, 1000);    
    },
     cache: false
   });
}


$(document).ready(function() {
    chart = new Highcharts.Chart({
    chart: {
        renderTo: 'container',
        defaultSeriesType: 'spline',
        events: {
            load: requestData
        }
    },
    title: {
        text: 'Live Heartbeats data'
    },
    xAxis: {
        type: 'datetime',
        tickPixelInterval: 150,
        maxZoom: 20 * 1000
    },
    yAxis: {
        minPadding: 0.2,
        maxPadding: 0.2,
        title: {
            text: 'Value',
            margin: 80
        }
    },
    series: [{
        name: 'heartbeats data',
         data: []
       }]
    });        
});
        </script>