code: @Override
      public String[] getInstanceNameList(final String dsExecName) throws DevFailed {
          final DeviceData argin = new DeviceData();
          argin.insert(dsExecName);
          final DeviceData argout = database.command_inout("DbGetInstanceNameList", argin);
          return argout.extractStringArray();
      }
docs: Get the list of instance for an executable.(execute DbGetInstanceNameList
  on DB device)
  
  @param dsExecName
  The executable name
  @return the list of instance
  @throws DevFailed