hi i was making a start page, where one must register a personal code, as in password, to proceed to the main site. to check if the code has already been used by someone else, i used the mysql_num_rows() function, but somethings making it fail... this is where i define a function wich is causing the whole jam. ive tried echoeing here and there, turns out the line with the error is the one with the $count = mysql_num_rows($result) or die(mysql_error());... [code]PHP Code: <?php session_start(); require_once('vars.php'); //connectie maken met DB $db = mysql_connect("localhost", "dieetopmaat_be", "dieetDB") or die(mysql_error()); mysql_select_db(dieetopmaat_be, $db) or die(mysql_error()); function check_presence($table, $row, $value){ $sql = "SELECT * FROM $table WHERE $row = '$value'"; $result = mysql_query($sql) or die(mysql_error()); $count = mysql_num_rows($result) or die(mysql_error()); if($count >= 1) { return TRUE; }else { return FALSE; }[/code] thanks to anyone who replies! OranniS ps: dont mind the language, its written in dutch