I'm working on the Flutter app where users can save multiple addresses. Previously I used a real-time database and it was easier for me to push data in any child with a unique Id but for some reason, I changed to Firestore and the same thing want to achieve with firestore. So, I generated UUID to create unique ID to append to user_address
This is how I want
and user_address looks like this
And this is how it's getting saved in firestore
So my question Is how I append data with unique id do I have to create a collection inside users field or the above is possible?
Below is my code I tried to set and update even user FieldValue.arrayUnion(userServiceAddress) but not getting the desired result
var uuid = Uuid();
var fireStoreUserRef =
await FirebaseFirestore.instance.collection('users').doc(id);
Map locationMap = {
'latitude': myPosition.latitude,
'longitude': myPosition.longitude,
};
var userServiceAddress = <String, dynamic>{
uuid.v4(): {
'complete_address': completedAddressController.text,
'floor_option': floorController.text,
'how_to_reach': howtoreachController.text,
'location_type': locationTag,
'saved_date': DateTime.now().toString(),
'user_geo_location': locationMap,
'placeId': addressId
}
};
await fireStoreUserRef.update({'user_address': userServiceAddress});
If I use set and update then whole data is replaced with new value it's not appending, so creating a collection is the only solution here and If I create a collection then is there any issue I'll face?
You won't have any issues per se by storing addresses in a separate collection with a one-to-many relationship, but depending on your usage, you may see much higher read/write requests with this approach. This can make exceeding your budget far more likely.
Fortunately, Firestore allows updating fields in nested objects via dot notation. Try this:
var userServiceAddress = {
'complete_address': completedAddressController.text,
'floor_option': floorController.text,
'how_to_reach': howtoreachController.text,
'location_type': locationTag,
'saved_date': DateTime.now().toString(),
'user_geo_location': locationMap,
'placeId': addressId
};
await fireStoreUserRef.update({'user_address.${uuid.v4()}': userServiceAddress});
Related
I am working with Google Sheets, and I am trying to send data to my Firestore database. I have been able to write to Firestore from Google Sheets, but I can't seem to update a field without completely messing things up.
This is my current testing code:
function getFireStore() {
const email = "your#email.gserviceaccount.com"
const key = "-----BEGIN PRIVATE KEY-----\n your key here \n-----END PRIVATE KEY-----\n";
const id = "project_id";
var firestore = FirestoreApp.getFirestore(email, key, id);
var spreadsheet = SpreadsheetApp.getActive()
var sheet = spreadsheet.getActiveSheet()
var data = {
numIndividuals: sheet.getRange(23, individuals).getValue(),
numTeams: sheet.getRange(23, teams).getValue(),
schoolID: sheet.getRange(23, schoolID).getValue(),
uid: sheet.getRange(23, uid).getValue(),
};
firestore.createDocument("competitions/" + sheet.getRange(23, compId).getValue() + "/registration/abcdefg", data)
}
I understand after playing around with this that it will create a new subcollection titled "registration" with the document "abcdefg." The same thing happens when I use the updateDocument function, as well.
For the website that is reading and writing to this particular Firestore database, I use a similar function .update() to update the document with the correct information. However, in Google Sheets, while it would work the same way it is much more convoluted and tedious to do so.
The way that I came up with for trying to update the document was basically copying everything and adding in the new data.
However, this is seriously tedious and messy. Just copying the data that isn't changed looks like this:
var data = {
compDate: competitions.fields.compDate.stringValue,
contact: competitions.fields.contact.stringValue,
email: competitions.fields.email.stringValue,
grade: competitions.fields.grade.stringValue,
id: competitions.fields.id.integerValue,
maxTeams: competitions.fields.maxTeams.integerValue,
regDate: competitions.fields.regDate.stringValue,
schTeams: competitions.fields.schTeams.integerValue,
schedule: competitions.fields.schedule.stringValue,
site: competitions.fields.site.stringValue,
status: competitions.fields.status.stringValue,
timestamp: competitions.fields.timestamp.integerValue,
user: competitions.fields.user.stringValue,
year: competitions.fields.year.stringValue,
}
The data I want to change is a .mapValue with multiple fields where one of the fields can have multiple fields, which also have multiple fields.
Here's the hierarchy for the field I need to update:
first registration and first team
I know I could do multiple for-loops and whatnot on this, but my question is: is there a simpler way to do this, or do I have to go through and loop over everything to extract only what I want?
As a sidenote, what gets sent to Firestore if I put in the data I got from Firestore using the spread operator, without any editing, it includes every child from the above image. As in, I would have registration -> mapValue -> fields -> 0 -> mapValue -> fields -> etc. And, I don't want those mapValue and fields included, just that actual data (i.e. registration -> 0 -> {schoolID, uid, names, etc.}).
I am using Cloud Firestore as my database and I have collections of users where are stored basic information about user such as id, name, last name, email, company id.
Also I have collection of companies and in each company I have collection of tasks.
In each task I have one user assigned from collections of users (user data is replicated, so I have same data for that user as in collection users)
The problem is when I update user (change name or email...) from collection users because data is replicated that data is not changed in collection of tasks for that specific user.
Is there any way that using firestore when user from collection users is updated to automatically update it in collection of tasks?
This is quite a standard case in NoSQL databases, where we often denormalize data and need to keep these data in sync.
Basically you have two possible main approaches:
#1 Update from the client
When you update the "user" document, update at the same time the other documents (i.e. "tasks") which contain the user's details. You should use a batched write to do so: A batch of writes completes atomically and can write to multiple documents.
Something along the following lines:
// Get a new write batch
var batch = db.batch();
var userRef = db.collection('users').doc('...');
batch.update(userRef, {name: '....', foo: '....'});
let userTaskRef = db.collection('companies').doc('...').collection('tasks').doc('taskId1');
batch.update(userTaskRef, {name: '....'});
userTaskRef = db.collection('companies').doc('...').collection('tasks').doc('taskId2');
batch.update(userTaskRef, {name: '....'});
// ...
// Commit the batch
batch.commit().then(function () {
// ...
});
Note that you need to know which are "the other ("tasks") documents which contain the user's details": you may need to do a query to get these documents (and their DocumentReferences).
#2 Update in the back-end via a Cloud Function
Write and deploy a Cloud Function that is triggered when any "user" document is updated and which takes the value of this "user" document and update the "tasks" documents which contain the user's details.
Like for the first approach, you also need, in this case, to know which are "the other ("tasks") documents which contain the user's details.
Following your comment ("Is there any option to reference to another table or put foreign key?") here is a Cloud Function that will update all the ("tasks") documents that have their DocumentReference contained in a dedicated Array field taskRefs in the "user" doc. The Array members are of data type Reference.
exports.updateUser = functions.firestore
.document('users/{userId}')
.onUpdate((change, context) => {
const newValue = change.after.data();
const name = newValue.name;
const taskRefs = newValue.taskRefs;
const promises = taskRefs.map(ref => { ref.update({ name: name, foo: "bar" }) });
return Promise.all(promises);
});
You would most probably set the value of this taskRefs field in the "user" doc from your frontend. Something along the following lines with the JS SDK:
const db = firebase.firestore();
db.collection('users').doc('...').set({
field1: "foo",
field2: "bar",
taskRefs: [ // < = This is an Array of References
db.collection('tasks').doc('....'),
db.collection('tasks').doc('....')]
});
In Firestore, I have a collection of fruits containing documents with automatically generated ids, and a name property.
I want to insert a new fruit document, with an automatically generated id, and only if no other with the same name exists.
Inspired by this answer, I try this:
Edit: For the record, as detailed in the accepted answer: this code is NOT transactionally safe: it does NOT prevent race conditions which could insert the same fruit name under heavy load
const query = firestore.collection(`/fruits`).where("name", "==", "banana").limit(1);
await firestore.runTransaction(async transaction => {
const querySnapshot = await transaction.get(query);
if (querySnapshot.length == 0) {
const newRef = firestore.collection(`/fruits`).doc();
await transaction.create(newRef, { name: "banana" });
}
});
But I wonder: is newRef guaranteed to be un-used?
Otherwise, does the transaction automatically retries (due to the create failing) until success?
Otherwise, how can I insert my fruit?
Note: I use the node.js admin SDK, but I think the problem is the same with the javascript API.
Edit: here is how I do it finally:
const hash = computeHash("banana"); // md5 or else
const uniqueRef = firestore.doc(`/fruitsNameUnique/${hash}`);
try {
await firestore.runTransaction(async transaction => {
transaction.create(uniqueRef, {}); // will fail if banana already exists
const newRef = firestore.collection(`/fruits`).doc();
transaction.create(newRef, { name: "banana" });
});
} catch (error) {
console.log("fruit not inserted", error.message);
}
is newRef guaranteed to be un-used?
It is virtually guaranteed to be unique. The chances of two randomly generated document IDs is astronomically small.
See also:
Firestore: Are ids unique in the collection or globally?
Are Firestore ids unique across the whole db
One thing you should be aware of is that your code is not actually transactionally safe. There is nothing stopping two clients from adding a new fruit where name=banana in a race condition between the moment of the query and the moment the transaction actually creates the new document. Under low traffic situations it's probably OK, but you are taking a chance on that.
In fact, Firestore doesn't have a built-in way to ensure uniqueness of a document's field value. It will require a fair amount of extra work to implement that yourself, perhaps by using that field value as the unique key in another collection, and making sure that collection is part of a bigger transaction that deals with the documents in your fruits collection.
Is there a way to fetch document after documentID like
private fun fetchCollectoionnAfterDocumentID(limit :Long){
val db = FirebaseFirestore.getInstance()
var query:Query = db.collection("questionCollection")
.startAfter("cDxXGLHlP56xnAp4RmE5") //
.orderBy("questionID", Query.Direction.DESCENDING)
.limit(limit)
query.get().addOnSuccessListener {
var questions = it.toObjects(QuestionBO::class.java)
questions.size
}
}
I want to fetch sorted questions after a given Document ID. I know I can do it using DocumentSnapShot. In order to fetch the second time or after the app is resume I have to save this DocumentSnapshot in Preference.
Can It be possible to fetch after document ID?
startAfter - > cDxXGLHlP56xnAp4RmE5
Edit
I know I can do it using lastVisible DocumentSnapshot . But I have to save lastVisible DocumentSnapshot in sharedPreference.
When app launch first time 10 question are fetched from questionCollection. Next time 10 more question have to be fetched after those lastVisible. So for fetching next 10 I have to save DocumentSnapshot object in sharedPreference. Suggest me a better approach after seeing my database structure.
And one more thing questionID is same as Document reference ID.
There is no way you can pass only the document id to the startAfter() method and simply start from that particular id, you should pass a DocumentSnapshots object, as explained in the official documentation regarding Firestore pagination:
Use the last document in a batch as the start of a cursor for the next batch.
first.get().addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
#Override
public void onSuccess(QuerySnapshot documentSnapshots) {
=// Get the last visible document
DocumentSnapshot lastVisible = documentSnapshots.getDocuments()
.get(documentSnapshots.size() -1);
// Construct a new query starting at this document,
Query next = db.collection("cities")
.orderBy("population")
.startAfter(lastVisible) //Pass the DocumentSnapshot object
.limit(25);
// Use the query for pagination
}
});
See, here the lastVisible is a DocumentSnapshot object which represents the last visible object. You cannot pass only a document id. For more information, you can check my answer from the following post:
How to paginate Firestore with Android?
It's in Java but I'm confident you can understand it and write it in Kotlin.
Edit:
Please consider defining an order of your results so that all your pages of data can exist in a predictable way. So you need to either specify a startAt()/startAfter() value to indicate where in the ordering to begin receiving ordered documents or use a DocumentSnapshot to indicate the next document to receive, as explained above.
Another solution might be to put the document id into the document itself (as a value of a property) and order on it, or you can use FieldPath.documentId() to order by the id without having to add one.
You can also check this and this out.
There is one way to let startAfter(documentID) works.
Making one more document "get", then using the result as startAfter input.
val db = FirebaseFirestore.getInstance()
// I use javascript await / async here
val afterDoc = await db.collection("questionCollection").doc("cDxXGLHlP56xnAp4RmE5").get();
var query:Query = db.collection("questionCollection")
.startAfter(afterDoc)
.orderBy("questionID", Query.Direction.DESCENDING)
.limit(limit)
A simple way to think of this: if you order on questionID you'll need to know at least the value of questionID of the document to start after. You'll often also want to know the key, to disambiguate between documents with the same values. But since it sounds like your questionID values are unique within this collection, that might not be needed here.
But just knowing the key isn't enough, as that would require Firestore to scan its entire index to find that document. Such an index scan would break the performance guarantees of Firestore, which is why it requires you to give you the information it needs to perform a direct lookup in the index.
I want to add 2 collections in Firestore in React Native.
Like JOIN can be used to add 2 tables. Is there any alternative for JOIN in Firestore to add collections?
I want to add these 2 collections users and users_2
How can I do this? Please help
At the time of writing it is not possible to query documents across collections in Firestore (it is apparently a feature that is on the roadmap however, see this recent blog post https://cloud.google.com/blog/products/databases/announcing-cloud-firestore-general-availability-and-updates -see bullet point "More features coming soon"-).
So that means that you'll have to issue two queries (one for each table, to get all the collection docs) and join/combine their results in your front end.
Another approach would be to duplicate your data (which is quite common in NoSQL world) and create a third collection that contains copies of all the documents.
For this last approach you could use a Batched Write as follows (in Javascript):
// Get a new write batch
var batch = db.batch();
var docData = {email: 'test#gmail.com', fullname: 'John Doe'}
// Set the value of doc in users collection
var usersRef = db.collection('users').doc();
batch.set(usersRef, docData);
// Set the value of doc in the allUsers collection (i.e. the third collection)
var allUsersRef = db.collection('allUsers').doc();
batch.set(allUsersRef, docData);
// Commit the batch
return batch.commit().then(function () {
// ...
});