void set(BitSet notDeletedBitSet) {
      if (notDeletedBitSet.cardinality() == 0) {
        fill(true);
      } else {
        Arrays.fill(vector, 1);
        isRepeating = false;
        for (int setBitIndex = notDeletedBitSet.nextSetBit(0);
             setBitIndex >= 0;
             setBitIndex = notDeletedBitSet.nextSetBit(setBitIndex + 1)) {
          vector[setBitIndex] = 0;
        }
      }
    }
Calculates the min/max record key.
Structure in data is like this:
<op, owid, writerId, rowid, cwid, <f1, ... fn>>
The +1 is to account for the top level struct which has a
ColumnStatistics object in colsStats.  Top level struct is normally
dropped by the Reader (I guess because of orc.impl.SchemaEvolution)
@param colStats The statistics array
@return The min record key
ql/src/java/org/apache/hadoop/hive/ql/io/orc/VectorizedOrcAcidRowBatchReader.java