CODEWITHSUNDEEP
androidfirebasekotlinfirebase-realtime-database
Quinn
Quinn

Reputation: 9506

Correct way to structure firebase database by dates

So I have several objects I am monitoring on my server, and every hour I want to post the readings from these objects to my database. I need an easy way to have these so I can sort them by date in an array, get values from a specific day easily, and clean up old data that is no longer needed from a specific day.

I currently have two ideas of how I might structure my data:

1) Seperate it into chunks by the date parts

objects
    - objectA
        - 2020
            - 01
                - 22
                    - 01
                        - property1 : "Value at 1 o'clock on the 22nd of Jan, 2020"
                        - property2 : "Value at 1 o'clock on the 22nd of Jan, 2020"
                    - 02
                        - property1 : "Value at 2 o'clock on the 22nd of Jan, 2020"
                        - property2 : "Value at 2 o'clock on the 22nd of Jan, 2020"
                    ...
    - objectB
        ...

This method gives me the advantage of easily querying a specific day or month and getting the values from it. It also easily lets me clear old data from a specific day or month.

However the downside is I can't think of an easy way to query it to have the data in my app as a flat list sorted by time (which, for the most part, is how i need to data)

2) Store data as a flat list of dates to properties

objects
    - objectA
        - 2020:01:22:01
            - property1 : "Value at 1 o'clock on the 22nd of Jan, 2020"
            - property2 : "Value at 1 o'clock on the 22nd of Jan, 2020"
        - 2020:01:22:02
            - property1 : "Value at 2 o'clock on the 22nd of Jan, 2020"
            - property2 : "Value at 2 o'clock on the 22nd of Jan, 2020"
                    ...
    - objectB
        ...

This model makes it much easier to get the objects in the format I need them to be in the app, however now its harder to query just a specific day or month. And clearing old data from a specific day or month is not easy.

What is a good way of doing this in practice? Are either of my methods good or should I be doing something else entirely? If one is good than how do I solve the downside I have with it?

My app is written in Kotlin so is there an easy way in kotlin to query the database from option 1 and have it return in the for of a flat list?

Upvotes: 0

Views: 266

Answers (2)

Shahzain ali
Shahzain ali

Reputation: 1725

I think the best way is to store using time stamp, I always use timestamp where time and date dependencies occurs 

objects
    - objectA
        - 1579721879
            - property1 : "Value at 1 o'clock on the 22nd of Jan, 2020"
            - property2 : "Value at 1 o'clock on the 22nd of Jan, 2020"
        - 1579721964
            - property1 : "Value at 2 o'clock on the 22nd of Jan, 2020"
            - property2 : "Value at 2 o'clock on the 22nd of Jan, 2020"

or like this

objects
        - 1579721879 : "Value at 1 o'clock on the 22nd of Jan, 2020"
        - 1579721889 : "Value at 1 o'clock on the 22nd of Jan, 2020"
        - 1579721899 : "Value at 2 o'clock on the 22nd of Jan, 2020"

Upvotes: 0

Peter Haddad
Peter Haddad

Reputation: 80952

This way:

objects
    - objectA
        - 2020:01:22:01
            - property1 : "Value at 1 o'clock on the 22nd of Jan, 2020"
            - property2 : "Value at 1 o'clock on the 22nd of Jan, 2020"
        - 2020:01:22:02
            - property1 : "Value at 2 o'clock on the 22nd of Jan, 2020"
            - property2 : "Value at 2 o'clock on the 22nd of Jan, 2020"
                    ...
    - objectB
        ...

Is better than option 1, always favor using a flat data structure instead of a nested one. If you have difficulties retrieving the month or the day, you can add them both as a property:

objectA
    2020:01:22:01
        property1 : data
        month : 01
        day : 22

But you can also use getKey() and then use split to retrieve the month and day.

https://firebase.googleblog.com/2013/04/denormalizing-your-data-is-normal.html?m=1

Upvotes: 1

Related Questions