How do I iterate through all child nodes in firebase database using javascript?

Question

Below is how my firebase database is structured. I would like to iterate through all the nodes named details that are under the residents node and display the value stored under the name, say example 'first_name'. Assistance would be grateful.

{
  "nibebe-530edaddclose":{
    "Estate":{
        "WVLN5yN88oZSzgIl7JpfbiRadYq1":{
            "details":{},
            "residents":{
                "details":{
                    "-LsxA0DMx5EqUe6xSvvM":{
                        "block_number":, 
                        "email":, 
                        "first_name":, 
                        "house_number":, 
                        "last_name":, 
                        "password":, 
                        "phone_number":,
                    }
                }
            }
        }
        "XxWh0j0QYIUZ35chQqkemwnB3Mw1":{
            "details":{},
            "residents":{
                "details":{
                    "-LsuDQO699osHfqq5BIC":{
                        "block_number":, 
                        "email":, 
                        "first_name":, 
                        "house_number":, 
                        "last_name":, 
                        "password":, 
                        "phone_number":,
                    }
                }
            }
        } 
    } 
} 

}`

Thanks in advance

Answer 1

Do you mean, in this example, you would want to get the value of both first_name fields? There is unfortunately no trick to this, and no good way to do it. Firebase does not support querying and (in my experience) is not well-suited to this kind of use case. You will need to get a ref ( https://firebase.google.com/docs/reference/js/firebase.database.Reference ) to the first shared ancestor of these objects (in this case, Estate ) and manually iterate through them. Depending on the size of your data, this might be a lengthy operation, so you might need to consider batching, etc. in order to prevent this operation from blocking something else.