public List<String> filterUnExistDatabases(final List<String> databases) {
    return Objects.isNull(databases)
        ? Collections.emptyList()
        : databases.stream()
            .filter(database -> !isDatabaseExist(database))
            .collect(Collectors.toList());
  }
Filter the un-exist Databases.

@param databases the Databases to check
@return List of PartialPath the Databases that not exist
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/manager/partition/PartitionManager.java