PREV - Amazon Glue DataBrew
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PREV

Returns a new column, where each value represents a value that is n rows earlier in the source column.

Parameters

  • sourceColumn – The name of an existing column.

  • numRows – A value that represents n rows earlier in the source column. For example, if numRows is 3, then PREV uses the third-previous sourceColumn value as the new targetColumn value.

  • targetColumn – A name for the newly created column.

Example

{
    "Action": {
        "Operation": "PREV",
        "Parameters": {
            "numRows": "1",
            "sourceColumn": "age",
            "targetColumn": "age_PREV"
        }
    }
}