uses
  ..., DatabaseVersioning, ...;

procedure TMainForm.FormCreate(Sender: TObject);
var
  DBVer: TDBVersioning;
begin
  SQLite3Connection1.Open;

  DBVer := TDBVersioning.Create(SQLite3Connection1, SQLTransaction1);
  if DBVer.CurrentVersion > DBVer.LatestVersion then
  begin
    MessageDlg('Seems you use database file made with more recent version of application!', mtError, [mbOK], 0);
    Application.Terminate;
  end
  else if DBVer.UpgradeNeeded then
  begin
    try
      // Upgrade database schema
      DBVer.UpgradeToLatest;
    except
      on E: Exception do
      begin
        MessageDlg('db upgrade failed!' + sLineBreak + E.ToString, mtError, [mbOK], 0);
        Application.Terminate;
      end;
    end;
  end;
  DBVer.Free;

  // SQLQueries should be activated after their tables created on previous step
  ContactsSQLQuery.Open;
  GroupsSQLQuery.Open;
end;