Shoutbox

I want to post info from a form am i doing it right like this?

code:

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$sql= "UPDATE molly SET inhoud = $_POST['inhoud']";
mysql_query($sql) or die (mysql_error());

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EDIT: I'm using this but it gives an error, sorry i'm a real n00b , and yes i know i should read some books first, but i'm lazy ...

code:

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<?

include_once('connection.inc.php');
opendb();

$sql= "UPDATE 'molly' SET 'inhoud' = '$_POST['inhoud']'";
mysql_query($sql) or die (mysql_error());

?>

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