求高手一个多线程程序

//一个多线程的数据库查询的程序
unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Grids, DBGrids, Db, DBTables, StdCtrls, ADODB;

type
  TForm1 = class(TForm)
    ds1: TDataSource;
    dbgrd1: TDBGrid;
    ds2: TDataSource;
    dbgrd2: TDBGrid;
    btn1: TButton;
    qry1: TADOQuery;
    qry2: TADOQuery;
    procedure btn1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
  TQueryThread = class(TThread)
  private
//    FSession:TSession;
//    FDatabase:TDatabase;
    FQuery:TADOQuery;
    FDatasource:TDataSource;
    FQueryException:Exception;
    procedure ConnectDatasource;
    procedure ShowQryError;
  protected
    procedure Execute;override;
  public
    constructor Create(Query:TADOQuery;DataSource:TDataSource);virtual;
  end;
var
  Form1: TForm1;

implementation

constructor TQueryThread.Create(Query:TADOQuery;DataSource:TDataSource);
begin
  inherited Create(true);
//  FSession := Session ;
//  FDatabase := DataBase;
  FQuery := Query ;
  FDatasource := DataSource;
  FreeOnTerminate := true;
  Resume;
end;

procedure TQueryThread.Execute ;
begin
  try
    FQuery.Open;
    Synchronize(ConnectDatasource);
  except
    FQueryException := ExceptObject as Exception;
    Synchronize(ShowQryError);
  end;
end;

procedure TQueryThread.ConnectDatasource ;
begin
  FDatasource.DataSet := FQuery ;
end;

procedure TQueryThread.ShowQryError;
begin
  Application.ShowException(FQueryException);
end;

procedure RunBackgroundQuery(Query:TADOQuery;DataSource:TDataSource);
begin
  TQueryThread.Create(Query,DataSource);
end;
{$R *.DFM}

procedure TForm1.btn1Click(Sender: TObject);
begin
  RunBackgroundQuery(qry1,ds1);
  RunBackgroundQuery(qry2,ds2);
end;

end.