/**
   * Method declaration
   *
   * @param compact
   * @throws SQLException
   */
  void close(boolean compact) throws SQLException {

    if (Trace.TRACE) {
      Trace.trace();
    }

    if (bReadOnly) {
      return;
    }

    // no more scripting
    closeScript();

    // create '.script.new' (for this the cache may be still required)
    writeScript(compact);

    // flush the cache (important: after writing the script)
    if (cCache != null) {
      cCache.flush();
    }

    closeAllTextCaches(compact);

    // create '.backup.new' using the '.data'
    backup();

    // we have the new files
    pProperties.setProperty("modified", "yes-new-files");
    pProperties.save();

    // old files can be removed and new files renamed
    renameNewToCurrent(sFileScript);
    renameNewToCurrent(sFileBackup);

    // now its done completely
    pProperties.setProperty("modified", "no");
    pProperties.setProperty("version", jdbcDriver.VERSION);
    pProperties.setProperty("hsqldb.compatible_version", "1.7.0");
    pProperties.save();
    pProperties.close();

    if (compact) {

      // stop the runner thread of this process (just for security)
      stop();

      // delete the .data so then a new file is created
      (new File(sFileCache)).delete();
      (new File(sFileBackup)).delete();

      // tony_lai@users 20020820
      // The database re-open and close has been moved to
      // Database#close(int closemode) for saving memory usage.
    }
  }
  /**
   * When opening a database, the hsqldb.compatible_version property is used to determine if this
   * version of the engine is equal to or greater than the earliest version of the engine capable of
   * opening that database.
   *
   * <p>
   *
   * @return
   * @throws SQLException
   */
  boolean open() throws SQLException {

    if (Trace.TRACE) {
      Trace.trace();
    }

    if (!pProperties.checkFileExists()) {
      create();
      open();

      // this is a new database
      return true;
    }

    // todo: some parts are not necessary for ready-only access
    pProperties.load();

    sFileScript = sName + ".script";
    sFileCache = sName + ".data";
    sFileBackup = sName + ".backup";
    scriptChecker = new File(sFileScript);

    // tony_lai@users 20020820
    // Allows the user to modify log size from the properties file.
    iLogSize = pProperties.getIntegerProperty("hsqldb.log_size", iLogSize);

    String version = pProperties.getProperty("hsqldb.compatible_version");

    // fredt@users 20020428 - patch 1.7.0 by fredt
    int check = version.substring(0, 5).compareTo(jdbcDriver.VERSION);

    Trace.check(check <= 0, Trace.WRONG_DATABASE_FILE_VERSION);

    // save the current version
    pProperties.setProperty("hsqldb.version", jdbcDriver.VERSION);

    if (pProperties.isPropertyTrue("readonly")) {
      bReadOnly = true;

      dDatabase.setReadOnly();

      if (cCache != null) {
        cCache.open(true);
      }

      reopenAllTextCaches();
      runScript();

      return false;
    }

    boolean needbackup = false;
    String state = pProperties.getProperty("modified");

    if (state.equals("yes-new-files")) {
      renameNewToCurrent(sFileScript);
      renameNewToCurrent(sFileBackup);
    } else if (state.equals("yes")) {
      if (isAlreadyOpen()) {
        throw Trace.error(Trace.DATABASE_ALREADY_IN_USE);
      }

      // recovering after a crash (or forgot to close correctly)
      restoreBackup();

      needbackup = true;
    }

    pProperties.setProperty("modified", "yes");
    pProperties.save();

    if (cCache != null) {
      cCache.open(false);
    }

    reopenAllTextCaches();
    runScript();

    if (needbackup) {
      close(false);
      pProperties.setProperty("modified", "yes");
      pProperties.save();

      if (cCache != null) {
        cCache.open(false);
      }

      reopenAllTextCaches();
    }

    openScript();

    // this is an existing database
    return false;
  }