@HiveDecimalVersionV1
  public HiveDecimal pow(int exponent) {
    HiveDecimal result = new HiveDecimal(this);
    if (!fastPow(
        exponent, result)) {
      return null;
    }
    return result;
  }
Return the result of decimal^exponent
<p>
CONSIDER: Currently, negative exponent is not supported.
CONSIDER: Does anybody use this method?
storage-api/src/java/org/apache/hadoop/hive/common/type/HiveDecimal.java