@Override
    public DataType visit(RowType rowType) {
      List<StructField> fields = new ArrayList<>(rowType.getFieldCount());
      for (DataField field : rowType.getFields()) {
        StructField structField =
            DataTypes.createStructField(field.name(), field.type().accept(this), true);
        structField =
            Optional.ofNullable(field.description())
                .map(structField::withComment)
                .orElse(structField);
        fields.add(structField);
      }
      return DataTypes.createStructType(fields);
    }
For simplicity, as a temporary solution, we directly convert the non-null attribute to
nullable on the Spark side.
amoro-format-paimon/src/main/java/org/apache/amoro/formats/paimon/PaimonTypeToSparkType.java