Package org.apache.druid.query.rowsandcols.semantic

Class DefaultGroupPartitioner

java.lang.Object
org.apache.druid.query.rowsandcols.semantic.DefaultGroupPartitioner
All Implemented Interfaces:
GroupPartitioner
public class DefaultGroupPartitioner extends Object implements GroupPartitioner

  • Constructor Details

    • DefaultGroupPartitioner

      public DefaultGroupPartitioner(RowsAndColumns rac)

  • Method Details

    • computeGroupings

      public int[] computeGroupings(List<String> columns)
      Description copied from interface: GroupPartitioner
      Computes the groupings of the underlying rows based on the columns passed in for grouping. The grouping is returned as an int[], the length of the array will be equal to the number of rows of data and the values of the elements of the array will be the same when the rows are part of the same group and different when the rows are part of different groups. This is contrasted with the SortedGroupPartitioner in that, the groupings returned are not necessarily contiguous. There is also no sort-order implied by the `int` values assigned to each grouping.
      Specified by:
      computeGroupings in interface GroupPartitioner
      Parameters:
      columns - the columns to group with
      Returns:
      the groupings, rows with the same int value are in the same group. There is no sort-order implied by the int values.