public StageType getType() {
    return StageType.STATS;
  }
StatsTask implementation. StatsTask mainly deals with "collectable" stats. These are
stats that require data scanning and are collected during query execution (unless the user
explicitly requests data scanning just for the purpose of stats computation using the "ANALYZE"
command. All other stats are computed directly by the MetaStore. The rationale being that the
MetaStore layer covers all Thrift calls and provides better guarantees about the accuracy of
those stats.
ql/src/java/org/apache/hadoop/hive/ql/stats/BasicStatsTask.java