当没有检测到更多错误时，数据无法插入数据库

这是我的代码

我的if-else语句有问题还是插入有任何问题

if（isset（$_POST["添加"]）｛

    $name = $_POST["username"];
    $pass = $_POST["password"];
    $fname = $_POST["fname"];
    $lname = $_POST["lname"];
    $hph = $_POST["home"];
    $hp = $_POST["hp"];
    $mail = $_POST["email"];
    $add = $_POST["address"];
    $age = $_POST["age"];
    $pos = $_POST["position"];
    $dept = $_POST["dept"];

$result我用它来检查我的用户名

    $result=mysql_query("select*from employee where Emp_Username='$name'");
if($name==""||$pass==""||$fname==""||$lname==""||$hph==""||$hp==""||$mail==""||$add==""||$age==""||$pos==""||$dept=="")
        {
?>
             <script type="text/javascript">
                 alert("Please fill in all the required informations.");
             </script> 
<?php        
        }
elseif(empty($errors)===true)
        {                   
                     if (!preg_match("/^[A-Z][a-zA-Z -]+$/i",$_POST['fname'])) 
                     {
                        $fnameErr= 'Invalid key has been input*';   
                     } 
                     if (!preg_match("/^[A-Z][a-zA-Z -]+$/i",$_POST['lname']) )
                     {
                        $lnameErr= 'Invalid key has been input*';           
                     }
                     if (filter_var($mail, FILTER_VALIDATE_EMAIL) === false) 
                     {
                        $mailErr = 'A valid email address is required*';    
                     }
                    if (!preg_match('/^[0-9]{1,}/', $_POST['age'])) 
                     {
                        $ageErr = 'Only can be numeric*';               
                     }
                    if (!preg_match("/^[a-zA-Z0-9 _.,:'"'']+$/i", $_POST['address'])) 
                     {
                        $addErr = 'Address must be letters and numbers*';               
                     }
                     if (!preg_match("/^[0-9]{2,2}[-][0-9]{7,7}$/", $_POST['home'])) 
                     {
                        $hphErr= 'Phone must comply with this mask: 04-4XX1234*';               
                     }
                    if (!preg_match("/^[0-9]{3,3}[-][0-9]{7,7}$/", $_POST['hp'])) 
                     {
                        $hpErr= 'Phone must comply with this mask: 014-XXX1234*';               
                     }
                    if(strlen($name)<4)
                    {
                        $nameErr = 'Your username must between 4 to 12 characters*';
                    }
                    if (strlen($pass) < 6) 
                    {
                        $passErr = 'Your password must be at least 6 characters*';              
                    }        
        }
elseif(mysql_num_rows($result)==0)

如果$result==0，那么我的数据将插入到员工表中，但它不能工作

        {
                mysql_query("insert into employee(Dept_ID, Emp_Address, Emp_Age, Position, Emp_Username, Emp_Password, Emp_Fname, Emp_Lname, ContactNo_Home, ContactNo_HP, Emp_Email) 
                values('$dept','$add','$age','$pos','$name','$pass','$fname','$lname','$hph','$hp','$mail')");
        ?>
                        <script type="text/javascript">
                         alert('Registered successfully!');
                        </script>
        <?php
        }
        else
        {
        ?>
                        <script type="text/javascript">
                        alert("Username already in use!");                                                                           
                        </script>
        <?php    
        }
}

希望有人能帮我找出问题并解决它。非常感谢。