I have now :
$inhoud = $_POST['inhoud'];
if($inhoud == "") {
    echo $inhoud;
    $inhoud = NULL;
    echo $inhoud;
}
$sql = 'SELECT DISTINCT bestanden.id AS id,
               bestanden.uploader AS uploader,
               bestanden.name AS name,
               bestanden.mime AS mime,
               bestanden.size AS size,
               bestanden.created AS created,
               zoeken.open_id AS open_id,
               zoeken.woord AS woord
        FROM bestanden
        LEFT JOIN zoeken ON bestanden.id = zoeken.open_id 
        WHERE zoeken.woord = "' . $inhoud . '" AND
              bestanden.name LIKE "%' . $_POST['naam'] . '%" AND
              bestanden.mime LIKE "%' . $_POST['formaat'] . '%"
              AND bestanden.created LIKE "%' . $_POST['datum'] . '%";';
$result = mysql_query($sql);
But when I search and $inhoud is empty, I got no results because they dont have an empty( " " ) (inhoud)space there. Is it possible to use an if or something in my mysql_query?
 
     
     
     
     
     
     
    