日期未在数据库中保存正确的值

Question

我今天得到当前日期和年份的年份和月份，并在我的文本框中显示正确的值。但是，当我开始将其提交到数据库时，该值默认变为 2014，而不是文本框的值。似乎是什么问题？function YearMonth() {  var d = new Date();  var n = d.getFullYear();  var t = d.getUTCMonth()+1;  var x = n + "-" + t ;    document.getElementById("num").value = x;} <td><input type="text" id="num" name="num"></td></tr> <input type= "button" name= "button_go" onclick="YearMonth()" id= "button_go" value= "GO" /> <input type= "submit" name= "submit" id= "submit_form" value= "Submit" /><?php    $servername = "localhost";    $username = "root";    $password = "";    $dbname = "_db";        $connection = new mysqli($servername, $username, $password, $dbname);            if ($connection->connect_error) {                die("Connection failed: " . $connection->connect_error);            }       $count = $_POST['num'];       $sql = "INSERT INTO table (no)            VALUES ($count)";            if ($connection->query($sql) === TRUE)             {            }             else            {                echo "Error: " . $sql . "<br>" . $connection->error;            }