@Override
  public void configureJobConf(JobConf job) {
    super.configureJobConf(job);
    for (PartitionDesc partition : aliasToPartnInfo.values()) {
      PlanUtils.configureJobConf(partition.getTableDesc(), job);
    }
    Collection<Operator<?>> mappers = aliasToWork.values();
    for (IConfigureJobConf icjc : OperatorUtils.findOperators(mappers, IConfigureJobConf.class)) {
      icjc.configureJobConf(job);
    }
  }
For each map side operator - stores the alias the operator is working on
behalf of in the operator runtime state. This is used by reduce sink
operator - but could be useful for debugging as well.
ql/src/java/org/apache/hadoop/hive/ql/plan/MapWork.java