php脚本不执行mysql命令。为什么？在后端测试mysql脚本时，它可以正常工作。
谢谢你的建议！我考虑了这个事实。不管怎样。。我的查询如下所示，不起作用或不产生任何错误。插入到标记（id，tags，givetake，onoff，tagnumber）值（'1234'，'jjj'，'0'，'0'，'1'）
当它复制到数据库后端它的工作非常完美。。。

<?php

    require_once('XXXX.php');
    //Variables for Authentication.
    $server_key = md5("XXXXX");
    $server_auth = $_POST["XXXXX"];

    if($server_auth == $server_key)
    {

        //Established the connection to the mySQL server.
        $connection = new mysqli($server_name, $database_user, $database_password, $database_name);

        if($connection) 
        {
            //Variables for userdatabase.
            //$firstName = $_POST["userFirstName"];
            //$lastName = $_POST["userLastName"];
            //$email = $_POST["userEmail"];
            //$password = $_POST["userPassword"];

            $id = $_POST["id"];
            $tags = $_POST["tags"];
            $giveTake= $_POST["giveTake"];
            $onOff = $_POST["onOff"];
            $tagNumber = $_POST["tagNumber"];

            // echo $firstName . ' ' . $lastName;
            //Getting data from the database.

            echo("vor SQL insert");
            $sql = "INSERT INTO tags (id, tags, giveTake, onOff, tagNumber) VALUES ('".$id."','".$tags."','".$giveTake."','".$onOff."','".$tagNumber."')";
            echo $sql;
            $result = mysqli_query($connection, $sql);
            echo $result;

            if($result)
            {
                echo ("Success.");
            }
            else
            {
                die("Coo0nection Failed.".mysql_connect_error());
                echo("Cooonnection Failed.");
            }
        }
    }
    else
    {
        echo("Error.");
    }   
?>