firestore map key-value pairs randomly change order when retrieved from the database

user_8849802 0
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I have a button which runs the following code when it's clicked:

let dataReference = await db.collection("dog").doc("1").get()
let HashMap = dataReference.data().Annotations
console.log(HashMap)

My firestore database looks like this:

enter image description here

Whenever this function is run, it returns the proper dictionary, however, the ordering of the keys seems to change randomly. Here's a screenshot of my console logs when I pressed the button a bunch of times:

enter image description here

Why does the ordering of the key-value pairs change and is there a way to fix it?

google-cloud-firestore firebase
2 Answers

The Firestore SDK does not guarantee an order of iteration of document fields. What you see in the console is always lexically sorted by the code of the console itself. If you require a stable ordering, you should sort them yourself before iteration.

user_8071260

One workaround you can do is to have the order of the keys you want in an array. Because arrays are ordered it will maintain the order you desired. Then you take that key and use it in the dictionary. While the dictionary is out of order, you will be accessing each value in order by key.

user_160289740
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