private boolean validateSelectOperator(SelectOperator op) {
    List<ExprNodeDesc> descList = op.getConf().getColList();
    for (ExprNodeDesc desc : descList) {
      boolean ret =
          validateExprNodeDesc(
              desc, "Select",
              VectorExpressionDescriptor.Mode.PROJECTION,
              /* allowComplex */ true, /* allowVoidProjection */ true);
      if (!ret) {
        return false;
      }
    }
    return true;
  }
Decimal types can be specified with different precision and scales e.g. decimal(10,5),
as opposed to other data types which can be represented by constant strings.
The regex matches only the {@link serdeConstants#DECIMAL_TYPE_NAME} prefix of the type.
ql/src/java/org/apache/hadoop/hive/ql/optimizer/physical/Vectorizer.java