Give_Donate_Form::update_meta PHP Method

    private function update_meta($meta_key = '', $meta_value = '')
    {
        /* @var WPDB $wpdb */
        global $wpdb;
        if (empty($meta_key)) {
            return false;
        }
        // Make sure if it needs to be serialized, we do
        $meta_value = maybe_serialize($meta_value);
        if (is_numeric($meta_value)) {
            $value_type = is_float($meta_value) ? '%f' : '%d';
        } else {
            $value_type = "'%s'";
        }
        $sql = $wpdb->prepare("UPDATE {$wpdb->postmeta} SET meta_value = {$value_type} WHERE post_id = {$this->ID} AND meta_key = '%s'", $meta_value, $meta_key);
        if ($wpdb->query($sql)) {
            clean_post_cache($this->ID);
            return true;
        }
        return false;
    }