How to make a join query in Firebase Android -

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how can perform join query select chatid "users" node, , chatid message items "chats" table.

sample json: (1, 2, 134 , 155 random user id's)

{   "chats" : {     "-kd3x3y16ydqhwsbxr5k" : {       "-kd3x3y5zew00h29zg55" : {         "text" : "hello",         "timestamp" : "1458224515",         "userid" : 1       },       "-kd3x4b1rmbaktvsooyn" : {         "text" : "test",         "timestamp" : "1458224517",         "userid" : 1       }     },     "-kd3xlnulu6ixb85u41s" : {       "-kd3xlnv32fzduqlxr1v" : {         "text" : "bla",         "timestamp" : "1458224588",         "userid" : 134       }     }   },   "users" : {     "1" : {       "2" : {         "chatid" : "-kd3x3y16ydqhwsbxr5k"       }     },     "134" : {       "155" : {         "chatid" : "-kd3xlnulu6ixb85u41s"       }     }   } }


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