Mercator\Mapping::update PHP Method

    public function update($data)
    {
        global $wpdb;
        $data = (array) $data;
        $fields = array();
        $formats = array();
        // Were we given a domain (and is it not the current one)?
        if (!empty($data['domain']) && $this->data->domain !== $data['domain']) {
            // Does this domain exist already?
            $existing = static::get_by_domain($data['domain']);
            if (is_wp_error($existing)) {
                return $existing;
            }
            if (!empty($existing) && $existing->get_site_id() !== $data['site']) {
                // Domain exists already and points to another site
                return new \WP_Error('mercator.mapping.domain_exists');
            }
            $fields['domain'] = $data['domain'];
            $formats[] = '%s';
        }
        // Were we given an active flag (and is it not current)?
        if (isset($data['active']) && $this->is_active() !== (bool) $data['active']) {
            $fields['active'] = (bool) $data['active'];
            $formats[] = '%d';
        }
        // Do we have things to update?
        if (empty($fields)) {
            return false;
        }
        $where = array('id' => $this->get_id());
        $where_format = array('%d');
        $result = $wpdb->update($wpdb->dmtable, $fields, $where, $formats, $where_format);
        if (empty($result) && !empty($wpdb->last_error)) {
            return new \WP_Error('mercator.mapping.update_failed');
        }
        $old_mapping = clone $this;
        // Update internal state
        foreach ($fields as $key => $val) {
            $this->data->{$key} = $val;
        }
        // Update the cache
        wp_cache_delete('id:' . $this->get_site_id(), 'domain_mapping');
        wp_cache_delete('domain:' . $old_mapping->get_domain(), 'domain_mapping');
        wp_cache_set('domain:' . $this->get_domain(), $this->data, 'domain_mapping');
        /**
         * Fires after a mapping has been updated.
         *
         * @param Mercator\Mapping $mapping         The mapping object.
         * @param Mercator\Mapping $mapping         The previous mapping object.
         */
        do_action('mercator.mapping.updated', $this, $old_mapping);
        return true;
    }