OrderByRelBuilder addClusterBy(ASTNode clusterBy) throws SemanticException {
      addRelDistribution(clusterBy);
      for (Integer fieldIndex : hiveRelDistribution.getKeys()) {
        fieldCollations.add(new RelFieldCollation(
                fieldIndex, RelFieldCollation.Direction.ASCENDING, RelFieldCollation.NullDirection.FIRST));
      }
      return this;
    }
This method can be called at startup time to pre-register all the
additional Hive classes (compared to Calcite core classes) that may
be visited during the planning phase in the metadata providers
and the field trimmer.
ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java