javascript - How to update a specific(nth) child of a key in firebase -


i know firebase has basic query functionality orderby, limitto, startat, endat...., etc. updating has methods update, set. in case have structure this:

enter image description here

so, there list of keys on pin, how can update child pin of specific key javascript?

for example, want update pin of second key. has 20, , want set 30. please, keep in mind list have more 2 keys, maybe later want update child pin of fourth generated key.

how can this?

relative ordering "second" or "fourth" pretty useless here. if want update pin of node key -krno...ho can with:

firebase.database().ref("pin/`-krno...ho/pin").set(30);

if want update pin of user named cindy, first need query determine key:

firebase.database().ref("pin").orderbychild("name").equalto("cindy").once("value", function(snapshot) {   snapshot.foreach(function(user) {     user.ref.child("pin").set(30);   }); })

the loop in second snippet needed, since there can technically multiple users named cindy.


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