如何有效地从数组中批量插入和更新mongodb文档值？

Question

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

Answer 1

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.