Returning Firebase database Nodes with any child with certain value

Question

I have following structure, cities is an array.

-NodeX 
 -KtI6rv4Wf5eEZLLXqRp 
   name: MyName1  
   Description: My Desc1 
   Cities  
     0
      name:My City
      isBig: False 
    1    
      name:Your City
      isBig: True  
    2   
      name:His City   
      isBig: False 
-KtKHcUjNlBuZSY7_5kv  
  name: MyName  
  Description: My Desc  
  Cities  
    0
      name:My City   
      isBig: False   
    1
      name:Your City  
      isBig: False  
    2 
      name:His City 
      isBig: False
-Kuc1bpEcW2yJEq6OK72  
  name: MyName 
  Description: My Desc  
  Cities   
   0    
     name:My City 
     isBig: True  
   1    
     name:Your City
     isBig: True      
  2   
     name:His City 
     isBig: False

I want to get top level nodes having ANY city which is Big (isBig=True) i.e. I want to get following two nodes.

KtI6rv4Wf5eEZLLXqRp

Kuc1bpEcW2yJEq6OK72

Ideally, I want to use Polymerfire query element, but even if there is another solution, I would go with that.

There's no way in the Firebase Realtime Database to query such nested properties. You'll need to change your data structure to allow the query you want. See [my answer here for more](https://stackoverflow.com/questions/46801852/google-firestore-structuring-deeply-nested-ordered-data). — Frank van Puffelen, Oct 18 '17 at 14:21

score 0 · Answer 1 · answered Oct 18 '17 at 16:16

That's not possible you have to change your data structure.

Something like this would be the way to go:

-cities 
  -KtI6rv4Wf5eEZLLXqRp 
    0
      name:My City
      isBig: False 
    1    
      name:Your City
      isBig: True  
    2   
      name:His City   
      isBig: False 
-info
  -KtI6rv4Wf5eEZLLXqRp 
    name: MyName1  
    Description: My Desc1

Then you need to fetch your data.

Returning Firebase database Nodes with any child with certain value

1 Answers1