mORMot study notes 2-2 ways to query data

This example uses SqlServer

The first way the result in the Memo control ,, need to refer to SynCommons, SynDB, SynOleDb;

procedure TForm1.Button1Click(Sender: TObject);
var
  DbConn: TOleDBMSSQLConnectionProperties;
  strSql: string;
  rows: ISQLDBRows;begin
  DbConn := TOleDBMSSQLConnectionProperties.Create('127.0.0.1', 'ReportServer', 'sa', 'Sa123');
  strSql := 'SELECT r.RoleName, r.Description FROM Roles AS r';
  rows := DbConn.ExecuteInlined(strSql, True);
  if rows <> nil then
  begin
    memo1.Clear;
    memo1.Lines.BeginUpdate;
    while rows.Step() do
    begin
      Memo1.Lines.Add(rows.ColumnString('RoleName') + '-' + rows.ColumnString('Description'));
    end;
  end;
  Memo1.Lines.EndUpdate;
end;

The second way to return the data set to the DBGrid control, you need to referenceSynCommons, SynDB, SynOleDb, SynDBMidasVCL;

procedure TForm1.Button2Click(Sender: TObject);
var
  DbConn: TOleDBMSSQLConnectionProperties;
  ds: TSynDBDataSet;
begin
  DbConn := TOleDBMSSQLConnectionProperties.Create('127.0.0.1', 'ReportServer', 'sa', 'Sa123');
  ds := TSynDBDataSet.Create(nil);
  ds.Connection := DbConn;
  ds.CommandText := 'SELECT r.RoleName, r.Description FROM Roles AS r' ; 
  Ds.Open; 
  DataSource1.DataSet: = DS;
   // DS can not be otherwise released here results not shown 
End ;

The results of two ways