public static Hashtable<Long,Boolean> categories() throws SQLException {
		PreparedStatement s = null;
		Hashtable<Long,Boolean> table = new Hashtable<Long,Boolean>();
		try {
			currentCon = DriverManager.getConnection(dbName);
			String query = "SELECT cid FROM products";
			s = currentCon.prepareStatement(query);
			rs = s.executeQuery();
			
			while (rs.next()) {
				table.put(rs.getLong("cid"),false);
			}
		} finally {
			if (rs != null) try {rs.close();} catch (SQLException ignore) {}
			if (s != null) try {s.close();} catch (SQLException ignore) {}
			if (currentCon != null) try {currentCon.close();} catch (SQLException ignore) {}
		}
		
		return table;
	}