MongoDB使用新的文档数组更新文档数组

Question

It is possible to insert an array of objects, but not possible to update them. You have to remove them and then insert them. I don't want to have to remove and then insert them, because if the remove goes well but then the insert has an error, the data is lost. How can I update an array (all documents) in a collection, properly?

Inserting array of documents:

collection.insert(arrToInsert, function(err, results){
    console.log(results.ops);
});

Updating inserted array (not good):

collection.remove({}, function(err){
    collection.insert(arrUpdated, function(err, result) {
        console.log(results.ops);
    });
});

I have tried using collection.update but this does not allow an array.

edit: For example: Insert this array:

[
    {_id:0,name:"Harry"},
    {_id:1,name:"Jacob"},
    {_id:2,name:"Bob"}
]

and then, change it to this:

[
    {_id:0,name:"Dennis"},
    {_id:1,name:"Peter"},
    {_id:2,name:"Ghandi"}
]

My actual case is a bit more complicated, because the array has another key/value pair, and can be changed in many ways.

Answer 1

You mean .bulkWrite() , which allows multiple update operations ( Insert/Update/Remove) on the same collection in a single batch request. It actually is what modern drivers really call when either .insert() or .insertMany() is called with an array of documents.

Your new update would be:

var arrToUpdate = [
    {_id:0,name:"Dennis"},
    {_id:1,name:"Peter"},
    {_id:2,name:"Ghandi"}
];

collection.bulkWrite(
  arrToUpdate.map( d => ({
    "replaceOne": {
      "filter": { "_id": d._id },
      "replacement": d
    }
  })),
  function(err,result) {
    console.log(result)
  }
)

Where replaceOne is essentially an "update" without using any modifiers such as $set .

The point is that just like .insert() with an array or .insertMany() , the database receives only one request and response, but there are multiple operations in that request.