code: public static void unRegisterH2GISFunctions(Connection connection) throws SQLException {
          Statement st = connection.createStatement();
          for (Function function : getBuiltInsFunctions()) {
              unRegisterFunction(st, function);
          }
          unRegisterGeometryType(connection);
      }
docs: Unregister spatial type and H2GIS functions from the current connection.
  
  @param connection Active H2 connection with DROP ALIAS rights
  @throws java.sql.SQLException