Question

I’ve got a strange problem. There are 2 queries.

$sql = "SELECT  `content_auftrag_id` 
        FROM `content` 
        WHERE `content_id` = '".$content_id."' LIMIT 1";
    $ergebnis = $db->prepare( $sql );
    $ergebnis->execute();
    $ergebnis->bind_result( $content_auftrag_vorhanden );

$content_auftrag_id = "test";
$sql = "UPDATE `content` SET `content_auftrag_id` = '".$content_auftrag_id."' 
        WHERE `content_id` = '".$content_id."'";
        $ergebnis2 = $db->prepare( $sql );
        $ergebnis2->execute();

When I use them both, then an error occurs for the second one. If I only run the the second, then it works fine. How can it be that both together cause an error?
All variables are there and correct.

Thanks!

Answer 1

You can only work on one prepared query at a time, so to speak. See Mysqli::execute() method:

“When using mysqli_stmt_execute(), the mysqli_stmt_fetch() function must be used to fetch the data prior to performing any additional queries.”

You can also use the store_result() method to remove this block as well to perform the next query.

Also, take heed from those who warn you about abusing prepared statements like your example. Though it works without error if you don’t actually have any parameters to bind to, it basically throws sql injection prevention out the window.