procedure TForm1.FormCreate(Sender: TObject);
const
 FileName = 'proba.db3';
var
 Path, SQL: String;
begin
 Path:=ExtractFilePath(Application.ExeName);
 IF Length(Path) > 1 then
    IF not(Path[Length(Path)] = '\')then Path:=Path+'\';

 IF FileExists(Path + FileName) = False then
    Begin
    LiteConnection1.Database:=Path + FileName;
    LiteConnection1.Options.Direct:=True;
    LiteConnection1.Options.ForceCreateDatabase:=True;
    LiteConnection1.Connected:=True;
    try
     SQL:='CREATE TABLE if not exists Tab_Sample ( '+
                         'ID INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,' +
                         'USERNAME CHAR(40) NOT NULL,' +
                         'DateReg DATE)';

     LiteConnection1.ExecSQL(SQL);
     SQL:='CREATE UNIQUE INDEX IDUSERDATE ON Tab_Sample (ID, USERNAME)';
     LiteConnection1.ExecSQL(SQL);

     LiteConnection1.Connected := False;
    except
     exit;
    end;
    end;//IF FileExists(Path + FileName) = False then

 LiteConnection1.Database:=Path + FileName;
 LiteConnection1.Options.Direct:=True;
 LiteConnection1.Options.ForceCreateDatabase:=True;
 try
  LiteConnection1.Connected := True;

  LiteTable1.SQL.Clear;
  LiteTable1.SQL.Add('SELECT * FROM Tab_Sample ORDER BY DateReg');
  LiteTable1.Open;
 except
  LiteConnection1.Connected := False;
 end;

end;

procedure TForm1.sBitBtn1Click(Sender: TObject);
begin
 LiteTable1.Append();
 LiteTable1.FieldByName('USERNAME').AsWideString:='User ' + IntToStr(LiteTable1.LastInsertId + 1);
 LiteTable1.FieldByName('DateReg').AsDateTime:=Now();
 LiteTable1.Post;

 ShowMessage('сен новый пользователь:' + 'ID = ' + IntToStr(LiteTable1.FieldByName('ID').AsInteger) + ' ' +
                                         'USERNAME = ' + LiteTable1.FieldByName('USERNAME').AsWideString + ' ' +
                                         'DateReg = ' + DateToStr(LiteTable1.FieldByName('DateReg').AsDateTime));
end;

 Ind:=Tbl.LastInsertId;

 Tbl.DisableControls();
 Tbl.Close();
 Tbll.Open();
 Tbl.Locate('ID', Ind, []);
 Tbl.EnableControls();

 Result:=Tbl.FieldByName('ID').AsInteger;