Update fields in nested objects in firestore documents?

Question

I have a data structure like:

I want to edit the value of "test" key in "first" object. I followed the document on https://firebase.google.com/docs/firestore/manage-data/add-data

But it did not work for me.

The nodejs code:

var setAda = dbFirestore.collection('users').doc('alovelace').update({
        first : {
            test: "12345"
            }
});

The result in firestore:

The "test2" key was gone. However, I only want to update the value of "test" and keep the "test2".

Any solution for this problem?

Peter Haddad · Accepted Answer · 2018-03-07 11:55:32Z

69

According to the link you provided, it says this:

If your document contains nested objects, you can use "dot notation" to reference nested fields within the document when you call update():

Therefore you need to use dot notation to be able to update only one field without overwriting, so like this:

var setAda = dbFirestore.collection('users').doc('alovelace').update({
    "first.test": "12345"
});

then you will have:

 first
  test: "12345"
  test2: "abcd"

answered Mar 7, 2018 at 11:55

Peter Haddad

81.2k26 gold badges148 silver badges149 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Tom Over a year ago

It is not clear from the documentation that ther is a difference in behavior when using the second type signature of DocumentReference.update, which results in a hard write: firebase.google.com/docs/reference/js/…

perepm Over a year ago

If I wanted to delete the test.first entry of the test map, would I need to perform a get() operation, delete it manually and then update the whole first map? Or is there a similar operation to delete nested fields in maps? @peter

Peter Haddad Over a year ago

@ppicom you need to do something like this update({"first.test" :firebase.firestore.FieldValue.delete()});

rendom Over a year ago

This is not working with .set({...}, {merge: true) for some reason.

Peter Haddad Over a year ago

have u tried the one below stackoverflow.com/a/57217966/7015400 @rendom?

Khaschuluu Munkhbayar · Accepted Answer · 2021-11-03 09:21:17Z

36

Peter's solution's great, but it's not works with dynamic key. Following code can works with it:

var nestedkey = 'test';
var setAda = dbFirestore.collection('users').doc('alovelace').update({
    [`first.${nestedkey}`]: "12345"
});

edited Nov 3, 2021 at 9:21

answered Feb 7, 2019 at 19:33

Khaschuluu Munkhbayar

4885 silver badges9 bronze badges

3 Comments

Borna Over a year ago

This is essentially the same as Peter's solution, except it uses template string...

y.selimdogan Over a year ago

Great thanks. I tried ${nestedKey} but it didnt worked until I cower it with [].

Sam Over a year ago

Tried to edit out the unnecessary "This code is far better" part and it erred with 'edit queue is full'

Joonsoo · Accepted Answer · 2022-05-22 23:50:55Z

14

If you don't want an exception that occur if 'first' field doesn't exist, try using set with {merge: true} option instead of update.

var setAda = dbFirestore.collection('users').doc('alovelace').set({
        first : {
            test: "12345"
        }
}, {merge: true});

Edit:

Thanks to @Shane Walker, the latest version(9.8.1) of Firestore has been changed so that update works the same as set with {merge: true} option.

Firebase JavaScript SDK Release Notes

edited May 22, 2022 at 23:50

answered Jul 26, 2019 at 10:18

Joonsoo

9671 gold badge16 silver badges17 bronze badges

1 Comment

Shane Walker Over a year ago

This method also works, but no exception is thrown if the field doesn't exist in the object, it's just added.

Alvin Konda · Accepted Answer · 2018-08-19 22:10:38Z

10

In case somebody is using TypeScript (like in Cloud functions for example) here is the code to update nested fields with dot notation.

var setAda = dbFirestore.collection('users').doc('alovelace').update({
    `first.${variableIfNedded}.test`: "12345"
});

answered Aug 19, 2018 at 22:10

Alvin Konda

3,2882 gold badges25 silver badges25 bronze badges

3 Comments

Alvin Konda Over a year ago

@Vino make sure you are using TypeScript. What is exactly the code you are using?

Chamanhm Over a year ago

When I attempt this approach like saveData[`picks.${matchId}.points`] = pickValue; where saveData is the Map that I end up writing into firebase. I get a new property created with the name "picks.94904.points" instead of writing into the map. I'm new to typescript so I'm assuming a syntax error. Any ideas why this happens?

Alvin Konda Over a year ago

@Chamanhm, you are over complicating your code. Try to make it simpler. Good luck

Lander · Accepted Answer · 2018-03-07 11:55:50Z

1

Try this one: Does it work like that?

var setAda = dbFirestore.collection('users').doc('alovelace').update({
        "first.test" : "12345"
});

answered Mar 7, 2018 at 11:55

Lander

613 bronze badges

Comments

Loheek · Accepted Answer · 2019-02-27 15:05:06Z

1

For those who need something more generic and recursive, here is a function that updates a Foo Firestore document non destructively with a typescript Partial :

private objectToDotNotation(obj: Partial<Foo>, parent = [], keyValue = {}) {
    for (let key in obj) {
        let keyPath = [...parent, key];
        if (obj[key]!== null && typeof obj[key] === 'object')
            Object.assign(keyValue, this.objectToDotNotation(obj[key], keyPath, keyValue));
        else
            keyValue[keyPath.join('.')] = obj[key];
    }
    return keyValue;
}

public update(foo: Partial<Foo>) {
    dbFirestore.collection('foos').doc('fooId').update(
        this.objectToDotNotation(foo)
    )
}

edited Feb 27, 2019 at 15:05

answered Feb 27, 2019 at 14:20

Loheek

1,9751 gold badge19 silver badges33 bronze badges

Comments

Azzaz · Accepted Answer · 2021-06-02 15:03:03Z

1

Use the set function and passing merge: true in options to update deeply nested fields without overwriting other fields.

const firstore = firebase.firestore()
const ref = firestore.doc('users/alovelace').set({
  first : {
    test: "12345"
  }
}, { merge: true })

With this method, you can update a field even if it's buried 20 levels deep.

answered Jun 2, 2021 at 15:03

Azzaz

1243 silver badges13 bronze badges

Comments

Coder Mark · Accepted Answer · 2019-08-10 18:13:02Z

0

For Swift 4

let dictionary:[String:Any] = ["first.test" : "12345"]
let plansDocumentReference = Firestore.firestore().collection("users").document("alovelace")              
plansDocumentReference.updateData(dictionary) { err in
                if let err = err {
                    print("Error updating document: \(err)")

                }}

You can update multiple fields by adding records to the dictionary as well as build variable based sub-keys by replacing the fixed text in the dictionary with string variable.

This technique also works to replace entire single key sub-blocks in the document by using a dictionary as the value for any key

answered Aug 10, 2019 at 18:13

Coder Mark

11 bronze badge

Comments

Frédéric Fortin · Accepted Answer · 2019-09-23 01:01:36Z

0

I was looking for a version in typescript without the extra params, having type completion in mind... Ended up with the following:

TS Playground example

function objectToDotNotation(obj: any): any {

    return Object.keys(obj).reduce( (dnObj, key) => {
        const value = obj[key];

        if (value !== null && typeof value === 'object') {            
            const childObj = objectToDotNotation(value);

            Object.keys(childObj).forEach( childKey => {
                dnObj = {...dnObj, [`${key}.${childKey}`]: childObj[childKey] };
            });
        } else {            
            dnObj = {...dnObj, [key]: value };
        }

        return dnObj;
    }, {});
}

answered Sep 23, 2019 at 1:01

Frédéric Fortin

1

Collectives™ on Stack Overflow

Update fields in nested objects in firestore documents?

9 Answers 9

5 Comments

3 Comments

1 Comment

3 Comments

Comments

Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

9 Answers 9

5 Comments

3 Comments

1 Comment

3 Comments

Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related