TAtlasAggregate

uses System.SysUtils, Atlas.Data, Atlas.Pivot;

procedure CompareAggregates(Sales: TAtlasTable);
const
  Names: array[TAtlasAggregate] of string = ('count', 'sum', 'minimum', 'maximum', 'average');
var
  Pivot: TAtlasPivot;
  Aggregate: TAtlasAggregate;
  Summary: TAtlasTable;
begin
  Pivot := TAtlasPivot.Create(nil);
  try
    for Aggregate := Low(TAtlasAggregate) to High(TAtlasAggregate) do
    begin
      Summary := Pivot.Summarize(Sales, 0, 1, 2, Aggregate);
      try
        // The last cell of the last row is the grand total.
        Writeln(Names[Aggregate].PadRight(9),
          Summary.Cell(Summary.ColumnCount - 1, Summary.RowCount - 1));
      finally
        Summary.Free;
      end;
    end;
  finally
    Pivot.Free;
  end;
end;