findAndModify fails with error: "Cannot update 'field1' and 'field1' at the same time

Question

I\'m trying to build MongoDB Java findAndModify query.

The main purpose is that I would like to set _id in insert query by myself.

Here is m

Answer 1

The essential problem here is this:

db.collection.update(
   { "type": "group" },
   { 
      "$set": { "mygroup": "value" }
      "$setOnInsert" { "mygroup": "value" }
   }
)

Which is basically what you are trying to do.

You cannot address the same field in a $set operation as a $setOnInsert operation.

There is a general problem in the logic that causes the error you are experiencing.