I am working on angular 5 with firebase firestore.I inserted data into fire-store collection/document/collection/document/collection/document then set data the last document.But at the time retrieving data I am giving only first collection name then I want complete root data.but I am getting only field in it.
https://firebase.google.com/docs/firestore/query-data/get-data
checkout:List subcollections of a document
As we know querying in Cloud Firestore is shallow by default. This type of query isn't supported, although it is something Google may consider in the future.
Related
User0 has a has runbooks stored in
/Runbook/user0/runbooks/0...n
UserX has runbooks stored at
/Runbook/userX/runbooks/0...n
UserX would like to include user0/runbooks/55 in his runbooks collection but doesn't want to move a copy into the runbooks collection. Is there a way to add a document into UserX's runbooks collection that will point to user0's 55 document?
You can simply store enough information about the document in a field (for example, its ID or its full path). Or you can store a reference type field that also essentially just contains the full path of the document.
See also:
Documentation
What is Firebase Firestore 'Reference' data type good for?
How to get the referenced data from a Firebase Firestore reference?
There is no type of document that itself is just a reference to another document. References are only valid as a document field type. You will have to model your data to account for this fact.
Is there a way to add a document into UserX's runbooks collection that
will point to user0's 55 document?
No. There is not. Duplicate data is common in document databases like Firestore, or Real Time Database. The correct thing to do is to duplicate the data.
How does one filter a Firestore collection by a document reference in the web console? For example, I have a collection that references another collection document called challenges.
But no matter what combination I use to try to filter that collection by the challenge ID it returns no results. I need to be able to do this so I can look at all of the documents in this collection that reference back to that particular challenge reference.
I am assuming this is possible in the console, but maybe it is not?
I use this code to get a collection snapshot from Firestore.
firestore().collection('project').where('userID', '==', authStore.uid).onSnapshot(onResult, onError);
This returns a huge amount of data, but I only need a few fields. Is it possible to query only a specific field? For example, if I only need the projectName and the creationDate fields.
Is it possible to query only a specific field?
No, that is not possbile. A Firestore listener fires on the document level. This means that you'll always get the entire document.
For example if I only need the projectName and the creationDate fields.
You cannot only get the value of a specific set of fields. It's the entire document or nothing. If you, however, only need to read those values and nothing more, then you should consider storing them in a separate document. This practice is called denormalization, and it's a common practice when it comes to NoSQL databases.
You might also take into consideration using the Firebase Realtime Database, for the duplicated data.
So few day ago I moved my apps posts to cloud firestore from realtime database because of the more flexable querying that firestore apparently has. I have been modifying my code to work with firestore as the new database. Now I ran into a problem. How can I retrieve every document within "Posts" collection that has "Likes" collection that contains a specifically named document? I don't know if that makes sense so here's an image showcasing the problem:
I had a working query for firebase realtime database but can't figure out how to do it with firestore. Is it possible or do I have to change the structure of my database? If I do have to change the structure, what would be the most convenient way of getting the same result?
This is currently not possible with collection group queries. You might be tempted to put a filter on the query for FieldPath.documentId() == 'your-doucment-id', but that just isn't supported. FieldPath.documentId() is actually a token that refers to to fully unique document id, which includes the entire path of the document.
The workaround is to store the document ID as a field in the document, and filter on the contents of that field instead. So, if the document had a field called id with the ID of the document, you could query for collectionGroup("Likes").whereEquals('id', 'your-document-id').
I'd like my web app router slugs to correspond to my Firestore documents data.
For example:
www.mysite.com/restaurants/burger-king
/restaurants <- Firestore Collection
/restaurants/mcdonalds <- Firestore Document
/restaurants/burger-king <- Firestore Document
This is easy enough, as I can assign the name as a slug-friendly UID in Firestore. The difficulty arises with CRUD functionality. I need to be able to rename my item titles, but Firestore does not permit you to rename indexes, which is the issue I'm facing.
One SO solution I saw was to delete the old record and creates a new one at the updated index. That's problematic for me, because sub-collections would be hard to transfer from the client side.
Are there more elegant solutions?
You don't have to identify a document by its ID. If you're able to ensure uniqueness of a document field value, you could instead query a collection for an ID value in a known field, then use the results of that query to satisfy your REST API. Then, you can change the value of that document field as often as you want, in order to satisfy required changes to the public API.