firebase-database-dotnet | C # library for Firebase Realtime Database | Database library

There is no configuration for this. You will have to somehow maintain a count, check the count on each new child, and delete the oldest child if the count exceeds your threshold. If you don't want to write this code, you could look into using the RTDB Limit Child Nodes extension which contains some code that might do what you want.

I eagerly waited for an answer, refreshing the page so many times. Luckily i found a way to do it.

To create an email key, first replace any characters like ". $ # [ ]" in your email string because Firebase does not support them. Or another way is to convert the string to byte array then to base64. The good thing is that base64 string alphabet does not have those characters, so it is safe to use it.

Then in the AddUser function, put the base64 email key child under the main child "User2". The main child can be of any name, im going to change it after this. The "PutAsync" will put the new user data inside that email child.

Please take note, the "User" as seen in the AddUser function parameter, is a class i defined that has user properties like firstname, lastname, email, country, phone and so on.

If you add an observer on /dinosaurs then any time something happens under dinosaurs you get the whole JSON of /dinosaurs. There is no way to only get the changes, even though most native Firebase SDK actually only synchronize the things that have changed on the wire.

If you want to get more granular data, consider storing that more granular data. For example, if you want to only process the delta in your client, consider storing only the delta in a separate node in your database. And then when you listen to just that node, you'll only get the updates and can process those.