copy.md

Copy

The COPY directive copies values from a source column into a destination column.

Syntax

copy <source> <destination> [<force>]

The COPY directive copies data from the <source> column into the <destination> column.

If the <destination> column already exists, the <force> option can be set to true to override any existing data in that column. By default, the <force> option is set to false.

Usage Notes

The COPY directive will copy data from <source> if and only if <source> column exists. If the <source> doesn't exist in the record, the execution will fail with an error.

Copying makes a deep copy of the source into the destination. The type of data from the source in the destination column is maintained as-is.

Example

Using this record as an example:

{
  "id": 1,
  "timestamp": 1234434343,
  "measurement": 10.45,
  "isvalid": true,
  "message": {
     "code": 132,
     "text": "Failure in the temperature sensor"
  }
}

Applying these directives:

copy timestamp datetime
copy message status

would result in this record:

{
  "id": 1,
  "timestamp": 1234434343,
  "datetime": 1234434343,
  "measurement": 10.45,
  "isvalid": true,
  "message": {
     "code": 132,
     "text": "Failure in the temperature sensor"
  },
  "status": {
      "code": 132,
      "text": "Failure in the temperature sensor"
  }
}