What is updateOne in MongoDB?

In MongoDB, updateOne() method updates a first matched document within the collection based on the given query. When you update your document the value of the _id field remains unchanged. This method updates one document at a time and can also add new fields in the given document.

What is the difference between update and updateOne in MongoDB?

updateMany: updates all the documents that match the filter. updateOne: updates only one documnet that match the filter.

What is the difference between updateOne and findOneAndUpdate?

findOneAndUpdate returns a document whereas updateOne does not (it just returns the _id if it has created a new document). I think that’s the main difference. So the use case of updateOne is when you don’t need the document and want to save a bit of time and bandwidth.

What does the filter in the syntax DB collection updateOne filter data option })?

In this syntax: The filter is a document that specifies the criteria for the update. If the filter matches multiple documents, then the updateOne() method updates only the first document. If you pass an empty document {} into the method, it will update the first document returned in the collection.

Is Upsert atomic MongoDB?

1 Answer. Upsert is not atomic. This is insinuated by the Mongo documentation: https://docs.mongodb.org/v3.0/reference/method/db.collection.update/. To avoid inserting the same document more than once, only use upsert: true if the query field is uniquely indexed.

Why MongoDB uses BSON?

BSON is the binary encoding of JSON-like documents that MongoDB uses when storing documents in collections. It adds support for data types like Date and binary that aren’t supported in JSON.

Is MongoDB update deprecated?

Like remove() , the update() function is deprecated in favor of the more explicit updateOne() , updateMany() , and replaceOne() functions. You should replace update() with updateOne() , unless you use the multi or overwrite options. update is deprecated. Use updateOne, updateMany, or bulkWrite instead.

What is the difference between remove and delete in MongoDB?

They do the same. The difference is the values that return.

Is findOneAndUpdate Atomic?

With the exception of an unindexed upsert, findOneAndUpdate() is atomic. That means you can assume the document doesn’t change between when MongoDB finds the document and when it updates the document, unless you’re doing an upsert.

Can we update _ID in MongoDB?

You cannot update it. You’ll have to save the document using a new _id , and then remove the old document.

What is Upsert in MongoDB?

In MongoDB, upsert is an option that is used for update operation e.g. update(), findAndModify(), etc. If the value of this option is set to true and the document or documents found that match the specified query, then the update operation will update the matched document or documents.

What is an Upsert operation?

Noun. upsert (plural upserts) (computing, databases) An operation that inserts rows into a database table if they do not already exist, or updates them if they do.