Ios 向Firebase规则添加索引

我正在使用GeoFire根据用户的当前位置从Firebase查询数据。我得到：

使用未指定的索引。考虑添加“.Noxon”：“G”AT / TO 您的安全规则可提高性能

在控制台中。下面是我的查询代码：

            ref = Database.database().reference()
            let geoFire = GeoFire(firebaseRef: ref)

            let center = CLLocation(latitude: (userLocation.coordinate.latitude), longitude: (userLocation.coordinate.longitude))

            let circleQuery = geoFire?.query(at: center, withRadius: 1)

            circleQuery?.observe(.keyEntered, with: { key, location in

                guard let key = key else { return }

                geoFire?.getLocationForKey(key, withCallback: { (location, error) in

                    let myAnnotation: MKPointAnnotation = MKPointAnnotation()
                    myAnnotation.coordinate = CLLocationCoordinate2DMake((location?.coordinate.latitude)!, (location?.coordinate.longitude)!);
                    self.currentLocationMapView.addAnnotation(myAnnotation)      
                })


                self.ref.child("services").child(key).observeSingleEvent(of: .value, with: { (snapshot) in

                    let value = snapshot.value as? NSDictionary
                    let servicename = value?["name"] as? String ?? ""
                    let address = value?["address"] as? String ?? ""

                    self.nameArray.append(servicename)
                    self.addressArray.append(address)


                    if (self.nameArray.count > 0) {
                        self.customTableView.reloadData();     
                    }

                })

            }) 

“我的Firebase规则”选项卡具有以下设置

"rules": {
    ".read": true,
        ".write": "auth != null"
          }

无论我在哪里插入“.indexOn”：“g”，我都会出错，无法保存规则。有什么帮助吗？

您要了解的要点

你要去的地方

"rules": {
  ".read": true,
  ".write": "auth != null",
  ".indexOn": ["g"]
}