I am building a search bar that retrieve documents from firestore that matches a string value. What I want is not retrieve documents that I have retrieved before, which are stored in a Set<documents>.
Is that possible in Firestore?
I think you're looking for the not-in clause, which allows you to specify values not to retrieve. If you want to do this based on the document ID, you can specify FieldPath.documentId() for the field name.
Related
There is a way to batch get documents after you specified exactly all the file paths using
https://firestore.googleapis.com/v1/projects/projectName/databases/dbName/documents:batchGet.
And there is a way to get all documents and their fields under a collection by sending a GET to https://firestore.googleapis.com/v1/projects/projectName/databases/dbName/documents/collectionName
I ideally want to make a batch request to get document fields for all documents under an array of collections. Is there a way to do this without knowing the document names of every document I intend to get?
Example
I have a structure like projects/projectName/databases/dbName/documents/Inventory/productId/variantId/*location*
Each productId is a document, and under this it has a collection for each variant, and within that collection are documents for each location, that contains a field count.
For a basket, I want to get all inventory counts for all inventory locations, for each productId/variantId in that bas
It is not possible to get all documents based on an array of collection names.
You can use a collection group query and search all collections of a given name, but then you must know the path of each document you want to read.
Alternatively, you can get all documents under a specific path, but then you can't filter by ID anymore, and the collections have to be under a path - not an array.
A question for the Firebase Firestore gurus out there.
I'm wanting to query a users collection for all documents where the bio field has a character length of <n
Is this possible?
I'm thinking this might have to be done post-query with some JS.
Firestore can only order/filter on values that are stored in the documents it returns. It cannot calculate any values, nor look values up.
So if you want to filter on the length of the bio, you'll have to store that value in a field in the document (e.g. bioLength) and update that each time you also update the bio.
With that field in place, you can then filter on it in a query.
I have the following structure in a Firestore collection. The "ranks" collection is updated with documents named after the timestamps. In each document, I have the same fields and values. How can I query all documents for a specific field without parsing the entire document? I.e. I want all values in all documents where field is "aave"?
I am new to Firestore and I've been trying this for several weeks now. I tried limiting with where and considered using sub collection group queries but in my case data is not stored in sub collections. Sorry, for not being able to provide more context, since I couldn't get much closer.
Queries select specific values, or ranges of values, of a known field. There is no support for dynamic field names in a query in Firestore.
But if you want to get all documents where the field aave exists/has any value, you can make use of the fact that in the sort order of values they always start with null. So to get all documents where the field aave exists/has any value, you could do:
firebase.firebase().collection("ranks").where("aave", ">=", null)
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 to query my database so that it returns Distinct Value of the chosen field. (Like SELECT DICTINCT) in MySQL.
Example: I queried my firstore Collection to get Documents where field messageTo isEqualTo 'Terry', this works fine but returns multiple documents with the same field 'chatID'.
I'd like to query the Collection to return Documents where field messageTo isEqualTo 'Terry' and making 'ChatID' field as DISTINCT value.
Firestore doesn't have anything that's equivalent to "select distinct". You will have to make a decision on the client by looking at the returned documents from a query.
It's worth noting, in a more general sense, that Firestore also does not offer any sort of projection view of documents when using client app APIs. Distinct selection is effectively a projection, because it only returns certain fields. Firestore document fetches and queries always return all the fields in a document.