private static void tryDelete(FileSystem fs, Path path) {
    try {
      fs.delete(path, true);
    } catch (IOException ex) {
      LOG.error("Failed to delete {}", path, ex);
    }
  }
Create row key and value object inspectors for reduce vectorization.
The row object inspector used by ReduceWork needs to be a **standard**
struct object inspector, not just any struct object inspector.
@param keyInspector
@param valueInspector
@return OI
@throws HiveException
ql/src/java/org/apache/hadoop/hive/ql/exec/Utilities.java