android - Firebase query for existence of keys -


i have following data structure (of events) , want query events particular user (user1) part of. 

{     "events":{         "event1":{             "users":{                 "user1":true,                 "user2":true             }         },         "event2":{             "users":{                 "user1":true             }         }     } }

the following query allows me events user1 part of in ways not allow me create db indexes.

starref.child("events").orderbychild("users/user1").start(true).end(true)

i'm looking way allows me (at best) query existence of key. example starref.child("events").orderbychild("users").haskey("user1")

to achieve this, recomand change database structure little bit, adding new node named events within each user. new node should this:

firebase-root    --- users      --- user1        --- events          --- event1: true          --- event2: true

to query events corespond particular user, add listener "firebase-root/users/user1/events" , events user belongs.

hope helps.


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