Code

<?php
echo "Starting code.php<br>";
$servername = "localhost";
$username = "myusername";
$password = "mypassword";
$dbname = "mydatabasename";

// Create Connection

$conn = new mysqli($servername, $username, $password, $dbname);

// Check Connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}
echo "Connected successfully<br>";

    // Prepare and Bind

    if ($stmt = $conn->prepare("INSERT INTO MyFieldData (field1, field2, field3, field4, field5, field6) VALUES (?, ?, ?, ?, ?, ?)")) {
        $stmt->bind_param("ssssss", $field1, $field2, $field3, $field4, $field5, $field6);
    } else {
        echo "Prepare() returned false! VAR_DUMP RESULTS: ";
        var_dump(error);
    }

    // Set Parameters & Filter

    $field1 = filter_input(INPUT_POST, 'u_username', FILTER_UNSAFE_RAW, FILTER_FLAG_STRIP_LOW);
    echo $username; // When I try this, nothing ever comes up on the screen...
    $field2 = $_POST['u_pwd'];
    $field3 = $_POST['u_email'];
    $field4 =  $_POST['u_growid'];
    $field5 = $_POST['u_world'];
    $field6 = $_POST['u_gender'];

    $stmt->execute();
?>