Una tabella pivot in poche righe.
Carica 100.000 righe con un solo ricalcolo, poi disponi le regioni per trimestre con la regione più grande per prima. La stessa API in Delphi, C++ Builder e C#.
dotnet add package esegece.sgcPivotGrid.WinForms
Versioni C++ Builder e C#
uses
Forms, Controls, SysUtils,
sgcPivotGrid_Types, sgcPivotGrid_Fields, sgcPivotGrid_VCL;
procedure CreatePivot(aForm: TForm);
const
Regions: array[0..3] of string = ('North', 'South', 'East', 'West');
var
vGrid: TsgcVCLPivotGrid;
vField: TsgcPivotField;
i: Integer;
begin
vGrid := TsgcVCLPivotGrid.Create(aForm);
vGrid.Parent := aForm;
vGrid.Align := alClient;
// load 100,000 rows, one recalculation at EndLoad
vGrid.Pivot.BeginLoad(True);
try
vGrid.Pivot.DefineColumn('Region', pvtText);
vGrid.Pivot.DefineColumn('Date', pvtDateTime);
vGrid.Pivot.DefineColumn('Sales', pvtFloat);
for i := 1 to 100000 do
vGrid.Pivot.AppendRow([Regions[i mod 4], EncodeDate(2025, 1, 1) + i mod 365,
10 + (i mod 97) * 1.5]);
finally
vGrid.Pivot.EndLoad;
end;
// layout: regions by quarter, the largest region first
vGrid.Pivot.BeginUpdate;
try
vField := vGrid.Pivot.AddField('Region', pvaRow);
vField.SortBy := pvsValue;
vField.SortOrder := pvoDescending;
vGrid.Pivot.AddField('Date', pvaColumn, pvdQuarter).Caption := 'Quarter';
vGrid.Pivot.AddDataField('Sales', pvfSum);
finally
vGrid.Pivot.EndUpdate;
end;
end;
