How do you query a Mongo db for rows containing a column with a specific type?

Question

I have a collection that has ended up with a column containing an updated timestamp, sometimes as a text field, sometimes as a date field. I am looking for the syntax to execute a query to find all rows that contain that field as a date type.

Answer 1

You can use $type with $not

Checking the not scenario. If type is not of string, then consider that doc.

playground

db.collection.find({
  "key": {
    $not: {
      $type: "string"
    }
  }
})