Which Is More Better Firebase Using Query Or Using Normal Reference
I noticed there are 2 types to retrieve a user data. Which one is better?
firebaseDatabase = FirebaseDatabase.getInstance(); usersDbRef = firebaseDatabase.getReference().child("Users"); //Using Query Query userQuery = usersDbRef.orderByChild("uid").equalTo(userUid); //Using Normal DatabaseReference dbRefUser = usersDbRef.child(userUid); //And then get user name and etc...
When you are using the following line of code:
usersDbRef = firebaseDatabase.getReference().child("Users");
You are getting all users that exist within
Users node without any limitations.
If you are using a query, you can add limitations and ordering to your items. For example, let's say you have a node that contains 1000 items. For sure you won't use a simple reference because getting 1000 items at once, will be a waste of bandwidth and resources, since no users are interested in 1000 items. What you can do instead is to add a call to
limit(50) and display only 50 items. So a query is needed to filter results and according to the use-case of your app, you can use one or the other in your project.
DatabaseReference dbRefUser = usersDbRef.child(userUid);
You tell Firebase that you are interested only in a single user object. So in this case, these is no need for a query, a simple reference will do the job.
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