How do you update a value in a document in mongodb atlas? - node.js

I have a database with values like this:
I also have a post method with the goal of updating the startBudget when a form is submitted.
All I want to do is update the startBudget number in the database. I tried doing that by using the updateOne function but it didn't change anything in the database. What am I doing wrong?

Figured it out. It turns out I needed to use save instead of updateOne. All good.

Related

Running a separate mongoose query to check a condition and start another one

I have a findOneAndUpdate mongoose query which is working perfectly fine. I want to use a findById query prior to it to check a certain condition before I run the findOneAndUpdate method and update a field.
So my solution has been to wrap the findOneAndUpdate method in a function and once the condition is by the findById query and passes,then call the function which will run the findOneAndUpdate query.
However when I do this I get waiting for localhost... until the browser sends a crash message. I know this must have something to do with the fact that both mongoose queries are asynchronous but I am not sure how to solve this.
Thanks.
Is there a reason why you cannot combine your queries? If you are already checking the document via findById then you can merge that criteria into your findOneAndUpdate.

How can I make mongoose to validate an entire 'outdated' MongoDB collection?

during the development of my app, i very often add custom and new fields to an existing schema, making the 'old' content in my mongodb 'incompelete' and missing the new fields. this leads sometimes to null content where it's required and it's in my use case very bad.
my question is what command/utility do i need to use to make mongoose validate my old documents, and in potential add those missing fields with pre-defined defaults to the old documents?
i remember reading something about that kind of functionality when i started learning how to use mongoose, but i just can't find it anywhere anymore..
thanks in advance :)
Amit

Mongoose bulk insert or update documents

I am working on a node.js app, and I've been searching for a way around using the Model.save() function because I will want to save many documents at the same time, so it would be a waste of network and processing doing it one by one.
I found a way to bulk insert. However, my model has two properties that makes them unique, an ID and a HASH (I am getting this info from an API, so I believe I need these two informations to make a document unique), so, I wanted that if I get an already existing object it would be updated instead of inserted into the schema.
Is there any way to do that? I was reading something about making concurrent calls to save the objects, using Q, however I still think this would generate an unwanted load on the Mongo server, wouldn't it? Does Mongo or Mongoose have a method to bulk insert or update like it does with insert?
Thanks in advance
I think you are looking for the Bulk.find(<query>).upsert().update(<update>) function.
You can use it this way:
bulk = db.yourCollection.initializeUnorderedBulkOp();
for (<your for statement>) {
bulk.find({ID: <your id>, HASH: <your hash>}).upsert().update({<your update fields>});
}
bulk.execute(<your callback>)
For each document, it will look for a document matching the {ID: <your id>, HASH: {your hash}} criteria. Then:
If it finds one, it will update that document using {<your update fields>}
Otherwise, it will create a new document
As you need, it will not make a connection to the mongo server on each iteration of the for loop. Instead a single call will be made on the bulk.execute() line.

How to get Post with Comments Count in single query with CouchDB?

How to get Post with Comments Count in single query with CouchDB?
I can use map-reduce to build standalone view [{key: post_id, value: comments_count}] but then I had to hit DB twice - one query to get the post, another to get comments_count.
There's also another way (Rails does this) - count comments manually, on the application server and save it in comment_count attribute of the post. But then we need to update the whole post document every time a new comment added or deleted.
It seems to me that CouchDB is not tuned for such a way, unlike RDBMS when we can update only the comment_count attribute in CouchDB we are forced to update the whole post document.
Maybe there's another way to do it?
Thanks.
The view's return json includes the document count as 'total_rows', so you don't need to compute anything yourself, just emit all the documents you want counted.
{"total_rows":3,"offset":0,"rows":[
{"id":...,"key":...,value:doc1},
{"id":...,"key":...,value:doc2},
{"id":...,"key":...,value:doc3}]
}

Delete document with an empty ID

I have a CouchDB database in production. One of the documents has been edited (in Futon by an other developer).
And it's lost it's ID (don't ask me how he did it).
So now the document's id is an empty string, which makes it impossible to edit or delete via Futon.
Is there a way I could hack into CouchDB to delete that document anyway ?
I couldn't delete the document. But the database itself could be deleted.
And I couldn't reproduce the bug in locale. The other developer says he just removed the _id param and saved. I don't know what happened in CouchDB when he did it. But when I do so, it only recreates a new document (as we'd expect it to do).
So I've been using couch_docs to retrieve the datas locally.
As the id is empty, couch_docs doesn't imports it. So you don't even need to delete it manually.
Then I reimport all the records in an other database. I change the references to the database name in my config and everything works fine.
Destroying the database is not a problem even though there's an empty id.
Technically, a document ID is immutable so actually changing the _id field is not directly possible. Perhaps another document was created as a copy of the first?
A bug in CouchDB 1.1.0 allowed update functions to create empty string IDs.
A similar question asks about this and I gave a walkthrough of deleting empty ids there.
I haven't tried it but LoveSeat is supposed to be able to open and edit couchedb files...
This can be caused (and fixed!) by some error checking CouchDB was missing for _update handlers, as explained in How do you delete a couchdb document with an empty "" document id?

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