public String getDatabaseName() {
    if (databaseName == null) {
      List<TsFileResource> resources = !seqResources.isEmpty() ? seqResources : unseqResources;
      databaseName = resources.isEmpty() ? null : resources.get(0).getDatabaseName();
    }
    return databaseName;
  }
TsFileResources used by read job.

<p>Note: Sequences under the same data region share two lists of TsFileResources (seq and
unseq).
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/read/QueryDataSource.java