We are trying to implement versioning of documents in mongodb for our project using nodejs. For this, while we perform the findOneAndUpdate command we want to find the difference between the existing document and the new values being updated into it. The returnNewDocument parameter returns the new document after updating is there any way to get the base document ( the one before update is performed). Or is there any better way to perform mongodb document versioning?
Related
I've been building a backend app with NodeJS and MongoDB.
Until today, I could successfully check every result of updateOne function.
But now, it returns this:
{"acknowledged":false,"modifiedCount":0,"upsertedId":null,"upsertedCount":0,"matchedCount":0}
The problem is, it returns this but it updates the document? How can I solve this bug?
From mongoDB documentation:
The method returns a document that contains:
matchedCount containing the number of matched documents
modifiedCount containing the number of modified documents
upsertedId containing the _id for the upserted document.
A boolean acknowledged as true if the operation ran with write concern or false if write concern was disabled
So you need to check modifiedCount for check the numeber of document you updateting.
If you need to update just one document i suggest to use findOneAndUpdate(filter, update)
I have a collection in mongoDB that hold 66000 documents on it, Now I want to add new filed to all theses document a uniqueID field which take this form S-1111 and the number increase for the next document
I have tried to make a call to DB and update each one in order but it take to much time because this is a lot of request to mongoDB , so is there is another way to do that fast
I am working with Node and mongoose
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.
I'm pulling data from a RETS(XML) feed and saving it in a local MongoDB using node and mongoose.
Periodically I need to update the documents and delete the inactive ones as well as add new ones. Rather than making multiple queries to Mongo or the RETS server, I was pulling both and looping through the data.
This works fine but is there a way to save the Mongoose results back to the database with updates and inserts? Or do I need to find each document and update it individually?
On MongoDB, to update multiple documents (not just one) using Mongoose you can use the multi option:
Model.updateMany({
size: 'lage'
}, {
$set: { size: 'large' }
});
See more on in the Mongoose documentation for updating documents and here
For completeness, If any one has multiple query conditions and want to add new fields for every matching documents of query condition then we can go with
var bulk = Person.collection.initializeUnorderedBulkOp();
bulk.find(query1).update(update1);
bulk.find(query2).update(update2);
bulk.execute(callback);
In following documentation, it is said that db.collection.initializeUnorderedBulkOp()
Initializes and returns a new Bulk() operations builder for a
collection. The builder constructs an unordered list of write
operations that MongoDB executes in bulk. MongoDB executes in
parallel the write operations in the list.
https://docs.mongodb.org/v3.0/reference/method/db.collection.initializeUnorderedBulkOp/
I have a Tags collection which contains documents of the following structure:
{
word:"movie", //tag word
count:1 //count of times tag word has been used
}
I am given an array of new tags that need to be added/updated in the Tags collection:
["music","movie","book"]
I can update the counts all Tags currently existing in the tags collection by using the following query:
db.Tags.update({word:{$in:["music","movies","books"]}}, {$inc:{count:1}}), true, true);
While this is an effective strategy to update, I am unable to see which tag values were not found in the collection, and setting the upsert flag to true did not create new documents for the unfound tags.
This is where I am stuck, how should I handle the bulk insert of "new" values into the Tags collection?
Is there any other way I could better utilize the update so that it does upsert the new tag values?
(Note: I am using Node.js with mongoose, solutions using mongoose/node-mongo-native would be nice but not necessary)
Thanks ahead
The concept of using upsert and the $in operator simultaneously is incongruous. This simply will not work as there is no way to different between upsert if *any* in and upsert if *none* in.
In this case, MongoDB is doing the version you don't want it to do. But you can't make it change behaviour.
I would suggest simply issuing three consecutive writes by looping through the array of tags. I know that's it's annoying and it has a bad code smell, but that's just how MongoDB works.