@HiveDecimalVersionV1
  public static HiveDecimalV1 create(String dec) {
    BigDecimal bd;
    try {
      bd = new BigDecimal(dec.trim());
    } catch (NumberFormatException ex) {
      return null;
    }
    bd = normalize(bd, true);
    return bd == null ? null : new HiveDecimalV1(bd);
  }
Default precision/scale when system is not able to determine them, such as in case
 of a non-generic udf.
storage-api/src/java/org/apache/hadoop/hive/common/type/HiveDecimalV1.java