Package dev.frostlake.executor.operators

Interface AggregateEvaluator

public interface AggregateEvaluator
Interface for evaluating a SELECT-list item (aggregate or grouped projection) on a group of rows, identified by its position in the operator's select-expression list (not by text).

  • Method Summary

    Modifier and Type
    Method
    Description
    Object
    evaluate(int selectItemIndex, List<Row> rows)
    Evaluate the select item at the given index on a group of rows.

  • Method Details

    • evaluate

      Object evaluate(int selectItemIndex, List<Row> rows)
      Evaluate the select item at the given index on a group of rows.
      Parameters:
      selectItemIndex - index into the operator's select-expression list
      rows - The group of rows to aggregate
      Returns:
      The result of the aggregation