@Override
  public boolean isSame(OperatorDesc other) {
    if (getClass().getName().equals(other.getClass().getName())) {
      LimitDesc otherDesc = (LimitDesc) other;
      return getLimit() == otherDesc.getLimit();
    }
    return false;
  }
not to print the offset if it is 0 we need to turn null.
use Integer instead of int.
ql/src/java/org/apache/hadoop/hive/ql/plan/LimitDesc.java