Realtime Database query with two generated fields

Question

I have the following DB structure, then I need get data filtered by "date" field. How do I do that?

root {
  places {
    $placeUid {
      $bookingUid {
        date: String
        name: String
      }
    }
  }
}

My query looks like that, and it doesn't work:

refPlaces = Firebase.database.getReference("places")
refPlaces.orderByChild("date").equalTo("14.10.2020").addValueEventListener(…)

try change this ref "refPlaces = Firebase.database.getReference("places")" for this one: refPlaces = Firebase.database.ref("places") or set const dbr = firebase.database(); dbr.ref('palces')..... — , Oct 07 '20 at 14:57
Does `orderByChild('$booking/date')` work? You are looking inside a dictionary's field. I am unsure if this is supported, and maybe you would be required to change your database format. — frunkad, Oct 07 '20 at 15:06
This might help: https://stackoverflow.com/a/59001994/3829706 — frunkad, Oct 07 '20 at 15:13
What you're doing isn't supported - you can't have two variable child names under the path to query. — Doug Stevenson, Oct 07 '20 at 15:44

score 1 · Accepted Answer · answered Oct 07 '20 at 16:38

Firebase queries work on a flat list of child nodes, where the value you order/filter on is in a fixed path under each direct child node. Since you have two dynamic levels under places, you won't be able to query for it.

The solution is to create a flat list of bookings for this use-case, with each booking then having the place Uid as a property in each booking.

For more on this, see:

Realtime Database query with two generated fields

1 Answers1