Get choosen categories from firebase database

I'm trying to get multiple categories from my firebase database, here is the structure:

category 1 = GCPVN-GCPVQ-GCPVR-GCPVP-GCPUZ-GCPUY-GCPUV-GCPVJ-GCPVM
category 2 = GCW2H-GCW2K-GCW2M-GCW2J-GCWRV-GCWRU-GCWRG-GCW25-GCW27

What I would like to do is to get categories by sorting if their key contains a specified string (for example: "GCPVN").

I don't know if there is a solution using "StartAt", "EndAt" and "EqualsTo".

I'm using Unity.

Firebase Realtime Database does not have an operator that checks for a certain string inside the key of a set of nodes. You can do a prefix match (so keys starting with a specific string) with startAt and endAt, but no contains operation.

If you want to read all nodes whose key 8starts with* GCPVN, you can do that with:

FirebaseDatabase.DefaultInstance
        .GetReference("1-1-2025")
        .OrderByKey()
        .StartAt("GCPVN")
        .EndAt("GCPVN~")

Also see the Firebase documentation on sorting and filtering data.

If your use-case requires a contains operation, you'll need to use a (or an additional) tool that supports that.

This has been covered quite a few times before, so also see:

• Firebase get all usernames & user Id starting with user entered character
• How to query firebase keys with a substring
• Firebase query - Find item with child that contains string
• How to check if firebase child contains any special value in JavaScript?
• How to query firebase keys with a substring