Calculate values dynamically when updating a document in mongosh-CodePudding

I'm trying to update some documents using the mongo shell in mongodb compass. I'm using the updateMany function to do so. I want to calculate some values when updating the field. for example

This is an example document

Account

  capital: 100,
  deposit: 0

I want to apply something like this

db.account.updateMany({}, {$set: {deposit: this.deposit   this.capital}})

but this is not working

CodePudding user response：

You want to use the aggregated pipeline updates syntax to achieve this, This is the only way to use existing document data within an update as a value. The syntax (in your case) remains quite similar, like so:

db.account.updateMany(
{},
[
  {
    $set: {
      deposit: {
        $add: [
          "$deposit",
          "$capital"
        ]
      }
    }
  }
])

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