How to save Delta of Clientdataset to database using delphi

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//ATableName-表名, AKeyField-主键，多个主键用;隔开，如 ;pid;times;  from：unit HlsImplBase;
[delphi] view plain copy
function THlsImplBase.UpdateTableData(ATableName, AKeyField: AnsiString; var AData: Variant): Boolean;  
var
  LSql: string;  
  LDataSet: TDataSet;  
  LProvider:  TProvider;  
  LErrCount: Integer;  
  I: Integer;  
begin
  Result := False;  
  if ATableName = '' then Exit;  
  if AKeyField = '' then Exit;  
  LSql := 'select * from ' + ATableName + ' where 1 = 2';  
  LDataSet := CreateDataSet(LSql);  
  if not Assigned(LDataSet) then Exit;  
  LProvider := TProvider.Create(nil);  
  LProvider.UpdateMode := upWhereKeyOnly;  
  LProvider.DataSet := LDataSet;  
  AKeyField := LowerCase(AKeyField);  
  for I := 0 to LDataSet.FieldCount - 1 do
  begin
    if (LowerCase(LDataSet.Fields[I].FieldName) = AKeyField) or
        (Pos(';' + LowerCase(LDataSet.Fields[I].FieldName) + ';', AKeyField) > 0) then
      LDataSet.Fields[I].ProviderFlags := LDataSet.Fields[I].ProviderFlags + [pfInKey]  
    else
      LDataSet.Fields[I].ProviderFlags := [];  
  end;  
  try
    try
      LProvider.ApplyUpdates(AData, -1, LErrCount);  
    except
    end;  
    Result := LErrCount = 0;  
  finally
    LDataSet.Free;  
    LProvider.Free;  
  end;  
end;