PHP ActionScript错误

I write PHP and ActionScript and connect them but result error

Here is the ActionScript

var filepath:String;

if (_url.indexOf("http") != 0) filepath = "http://localhost/adaptasi/";
else filepath = "../scripts/";

var send_lv:LoadVars = new LoadVars();
var result_lv:LoadVars = new LoadVars();

result_lv.onLoad = function(success:Boolean):Void {
   TextIsi1.text = result_lv;
}

send_lv.sendAndLoad(filepath + "morfologi.php", result_lv, "GET");

And here is the PHP

<?php
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "adaptasi";

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
} 

$sql = "SELECT * FROM materi";
$result = mysqli_query($conn, $sql);

{
    echo "Error: " . $sql . "<br>" . $conn->error;
}

$conn->close();
?>

and the result is error: Error SELECT * FROM materi & onLoad= type Function