php Update sql and Query

I want to do a query in php, output the data on the page and then modify it in the database.

How do I do that?

Currently I do it like this but it dose not work:

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

$sql = "SELECT * FROM pics WHERE id = '$id'";
$result = $conn->query($sql);
    // output data of each row
    while($row = $result->fetch_assoc()) {
       $dir = $row["dir"];
       $likes = $row["likes"];
    }

$sqlq = "UPDATE pics SET likes='$likes+1' WHERE id='$id'";

$conn->query($sqlq);

$conn->close();

But the like dose not add to the database.