public static StructObjectInspector setupPartitionOutputOI(AbstractSerDe serDe,
      StructObjectInspector tblFnOI) throws SerDeException {
    return (StructObjectInspector) ObjectInspectorUtils.getStandardObjectInspector(tblFnOI,
        ObjectInspectorCopyOption.WRITABLE);
  }
This can be used for functions with no parameters.
next() function in this impl does not fetch anything from rowContainer, thus saving IO.
It just increments the pointer to maintain iterator contract.
ql/src/java/org/apache/hadoop/hive/ql/exec/PTFPartition.java