Eclipse中没有MySQLi的自动完成功能

I have just written my first connection from PHP to mySQL using mySQLi. I noticed that there is no autocompletion for mySQLi objects. For example in this code there is no autocompletion for $result->num_rows and $result->data_seek($j). For php the autocompletion works as expected. What I am doing wrong?

<?php
require_once 'login.php';

$conn = new mysqli($hn,$un,$pw,$db);
if($conn->connect_error){
    echo"huhuhuhu";
}

$query = "select * from classics";
$result = $conn->query($query);
if(!$result){
    die("result je null");
}

$rows = $result->num_rows; // no autocompletion

for ($j = 0; $j<$rows; $j++){
    $result->data_seek($j); // no autocompletion
}

Since php is an interpreted language, the script would have to be executed in order for $result to have any values.

As far as i know, eclipse doesn't do that. (And I doubt there are many editors/ide's that do)