problem med udtræk fra database

Kan nogen fortælle mig hvad der er galt med denne kode.:

// extracts the object_time to add the $booking_end
        $sql = "SELECT object_time FROM rs_data_objects";
        $sql .= "WHERE object_id = " . $_REQUEST["object_id"] . ";";
        $temp = db_query($database_name, $sql);
        $temp_ = fetch_array($temp);
        $ObjectTime = $temp_["object_time"];

Jeg får denne fejl: Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource

// tabellen
CREATE TABLE `rs_data_objects` (
  `object_id` smallint(5) unsigned NOT NULL auto_increment,
  `rand_code` smallint(5) unsigned default NULL,
  `object_name` varchar(50) collate latin1_danish_ci NOT NULL default '',
  `family_id` tinyint(3) unsigned NOT NULL default '0',
  `manager_id` int(10) unsigned NOT NULL default '0',
  `misc_info` varchar(255) collate latin1_danish_ci default NULL,
  `object_time` varchar(255) collate latin1_danish_ci NOT NULL default '',
  PRIMARY KEY  (`object_id`),
  KEY `rand_code` (`rand_code`),
  KEY `family_id` (`family_id`),
  KEY `manager_id` (`manager_id`),
  KEY `object_time` (`object_time`)
) ENGINE=MyISAM AUTO_INCREMENT=8 DEFAULT CHARSET=latin1 COLLATE=latin1_danish_ci AUTO_INCREMENT=8 ;

// funktionen db_query og fetch_array

function db_query($db_name, $sql) {

        global $db_connection_type, $db_server_address, $db_user, $db_password;

        switch($db_connection_type) {
           
            case "odbc":
            $db_connection = odbc_connect($db_name, $db_user, $db_password);
            $result = odbc_exec($db_connection, $sql);
            break;

            case "mysql":
            $db_connection = mysql_connect($db_server_address, $db_user, $db_password);
            $result = mysql_db_query($db_name, $sql, $db_connection);
        }

        return $result;
    }

    function fetch_array($array) {
   
        global $db_connection_type;

        switch($db_connection_type) {

            case "odbc":
            $result = odbc_fetch_array($array);
            break;

            case "mysql":
            $result = mysql_fetch_array($array);
        }
       
        return $result;
    }