protected String getParamTypeString(int typeNum) {
    if (inputTypeInfos == null) {
      return "<input types is null>";
    }
    if (inputDataTypePhysicalVariations == null) {
      return "<input data type physical variations is null>";
    }
    return getTypeName(inputTypeInfos[typeNum], inputDataTypePhysicalVariations[typeNum]);
  }
Evaluate the child expressions on the given input batch.
@param vrg {@link VectorizedRowBatch}
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/VectorExpression.java