public void processRowSkewedIndex(RowSchema rowSch) {
    if ((this.skewedColNames != null) && (this.skewedColNames.size() > 0) && (rowSch != null)
        && (rowSch.getSignature() != null) && (rowSch.getSignature().size() > 0)) {
      List<ColumnInfo> cols = rowSch.getSignature();
      int hitNo = 0;
      for (int i = 0; i < cols.size(); i++) {
        int index = this.skewedColNames.indexOf(cols.get(i).getInternalName());
        if (index > -1) {
          hitNo++;
          SkewedColumnPositionPair pair = new SkewedColumnPositionPair(i, index);
          rowSkewedIndex.add(pair);
        }
      }
      assert (hitNo == this.skewedColNames.size()) : "RowSchema doesn't have all skewed columns."
          + "Skewed column: " + this.skewedColNames.toString() + ". Rowschema has columns: " + cols;
    }
  }
Match column in skewed column list and record position.
The position will be used in {@link FileSinkOperator} generateListBucketingDirName().
Note that skewed column name matches skewed value in order.

@param rowSch
ql/src/java/org/apache/hadoop/hive/ql/plan/ListBucketingCtx.java