表单数据正在提交，但不会进入mySQL

我的数据库连接是正确的，我可以选择和回显我的表的行。但是，我的表单数据没有更新我的数据库。我试图在同一页面上提交表单，所以我将该操作留空。这里是我的PHP：表单数据正在提交，但不会进入mySQL

<?php 
if (isset($_POST['submit'])) { 

    $con=mysqli_connect("localhost","hey","password!","dbname"); 
    $sql="INSERT INTO StudentList (StudentNum, LastName, FirstName, Address, City, State, Zip, Balance, FirstTermAttended) 
    VALUES('$_POST[inputID]','$_POST[inputLast]','$_POST[inputFirst]','$_POST[inputAddress]','$_POST[inputCity]','$_POST[inputState]','$_POST[inputZip]','$_POST[inputBalance]','$_POST[inputTerm]')"; 
    echo "It worked"; 
} 
?>

，在这里我的形式：

<form class="form-horizontal" role="form" method="post" action=""> 
       <div class="form-group"> 

        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputID" placeholder="Student ID Number"> 
        </div> 
       </div> 


       <div class="form-group"> 
        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputLast" placeholder="Last Name"> 
        </div> 
       </div> 

       <div class="form-group"> 
        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputFirst" placeholder="First Name"> 
        </div> 
       </div> 

       <div class="form-group"> 
        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputAddress" placeholder="Street Address"> 
        </div> 
       </div> 

       <div class="form-group"> 
        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputCity" placeholder="City"> 
        </div> 
       </div> 

       <div class="form-group"> 
        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputState" placeholder="State"> 
        </div> 
       </div> 

        <div class="form-group"> 
        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputZip" placeholder="Zip"> 
        </div> 
       </div> 

       <div class="form-group"> 
        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputBalance" placeholder="Current Balance"> 
        </div> 
       </div> 

       <div class="form-group"> 
        <div class="col-sm-offset-1 col-sm-10"> 
         <input type="text" class="form-control" id="inputTerm" placeholder="First Term Attended"> 
        </div> 
       </div> 

        <div class="modal-footer"> 
      <button type="button" class="btn btn-default" data-dismiss="modal">Close</button> 
      <input type="submit" value="Save Student Information" id="submit" name="submit" class="btn btn-primary"> 
     </div> 


      </form>

我也有这个在我的头，可以把它搞砸的事情了？

<?php 
// Create connection 
$con=mysqli_connect("localhost","hey","password!","dbname"); 

// Check connection 
if (mysqli_connect_errno()) 
    { 
    echo "Failed to connect to MySQL: " . mysqli_connect_error(); 
    } 
?>

来源

2014-02-06 evan

你是不是错过了'mysqli_query（）'？同时请清理从'$ _POST'收到的值 –

您提供的唯一命名输入是您的提交按钮。 –

[**如何防止PHP中的SQL注入？**]（http://stackoverflow.com/q/60174/1415724）<这是一条消息/线索。 ;-) –