private void updateTables4() {
    final FileInfoSet fileInfos = new FileInfoSet();
    final Cursor cursor = myDatabase.rawQuery("SELECT file_name FROM Books", null);
    while (cursor.moveToNext()) {
      fileInfos.check(ZLFile.createFileByPath(cursor.getString(0)).getPhysicalFile(), false);
    }
    cursor.close();
    fileInfos.save();

    myDatabase.execSQL(
        "CREATE TABLE RecentBooks("
            + "book_index INTEGER PRIMARY KEY,"
            + "book_id INTEGER REFERENCES Books(book_id))");
    final ArrayList<Long> ids = new ArrayList<Long>();

    final SQLiteStatement statement =
        myDatabase.compileStatement("SELECT book_id FROM Books WHERE file_name = ?");

    for (int i = 0; i < 20; ++i) {
      final ZLStringOption option = new ZLStringOption("LastOpenedBooks", "Book" + i, "");
      final String fileName = option.getValue();
      option.setValue("");
      try {
        statement.bindString(1, fileName);
        final long bookId = statement.simpleQueryForLong();
        if (bookId != -1) {
          ids.add(bookId);
        }
      } catch (SQLException e) {
      }
    }
    saveRecentBookIds(ids);
  }
  private void updateTables6() {
    myDatabase.execSQL("ALTER TABLE Bookmarks ADD COLUMN model_id TEXT");

    myDatabase.execSQL("ALTER TABLE Books ADD COLUMN file_id INTEGER");

    myDatabase.execSQL("DELETE FROM Files");
    final FileInfoSet infoSet = new FileInfoSet();
    Cursor cursor = myDatabase.rawQuery("SELECT file_name FROM Books", null);
    while (cursor.moveToNext()) {
      infoSet.check(ZLFile.createFileByPath(cursor.getString(0)).getPhysicalFile(), false);
    }
    cursor.close();
    infoSet.save();

    cursor = myDatabase.rawQuery("SELECT book_id,file_name FROM Books", null);
    final SQLiteStatement deleteStatement =
        myDatabase.compileStatement("DELETE FROM Books WHERE book_id = ?");
    final SQLiteStatement updateStatement =
        myDatabase.compileStatement("UPDATE Books SET file_id = ? WHERE book_id = ?");
    while (cursor.moveToNext()) {
      final long bookId = cursor.getLong(0);
      final long fileId = infoSet.getId(ZLFile.createFileByPath(cursor.getString(1)));

      if (fileId == -1) {
        deleteStatement.bindLong(1, bookId);
        deleteStatement.execute();
      } else {
        updateStatement.bindLong(1, fileId);
        updateStatement.bindLong(2, bookId);
        updateStatement.execute();
      }
    }
    cursor.close();

    myDatabase.execSQL("ALTER TABLE Books RENAME TO Books_Obsolete");
    myDatabase.execSQL(
        "CREATE TABLE Books("
            + "book_id INTEGER PRIMARY KEY,"
            + "encoding TEXT,"
            + "language TEXT,"
            + "title TEXT NOT NULL,"
            + "file_id INTEGER UNIQUE NOT NULL REFERENCES Files(file_id))");
    myDatabase.execSQL(
        "INSERT INTO Books (book_id,encoding,language,title,file_id) SELECT book_id,encoding,language,title,file_id FROM Books_Obsolete");
    myDatabase.execSQL("DROP TABLE Books_Obsolete");
  }