// Subsequent reads will reuse this buffer.
				p.buf[bufIdx] = make([]byte, p.shardSize)
			}
			// For the last shard, the shardsize might be less than previous shard sizes.
			// Hence the following statement ensures that the buffer size is reset to the right size.
			p.buf[bufIdx] = p.buf[bufIdx][:p.shardSize]
			n, err := rr.ReadAt(p.buf[bufIdx], p.offset)
			if err != nil {
				switch {

<img src="/img/tutorial/security/image01.png">

!!! check "Authorize button!"
    You already have a shiny new "Authorize" button.

    And your *path operation* has a little lock in the top-right corner that you can click.

And if you click it, you have a little authorization form to type a `username` and `password` (and other optional fields):

<img src="/img/tutorial/security/image02.png">

!!! note

* MySQL
* SQLite

In this example, we'll use **SQLite**, because it uses a single file and Python has integrated support. So, you can copy this example and run it as is.

Later, for your production application, you might want to use a database server like **PostgreSQL**.

!!! tip

Or it might be the case that you just prefer to take other courses because they adapt better to your learning style.

    private static final String NUMBER_OF_DATA_NODES = "number_of_data_nodes";
    private static final String NUMBER_OF_PENDING_TASKS = "number_of_pending_tasks";
    private static final String NUMBER_OF_IN_FLIGHT_FETCH = "number_of_in_flight_fetch";
    private static final String DELAYED_UNASSIGNED_SHARDS = "delayed_unassigned_shards";
    private static final String TASK_MAX_WAIT_TIME_IN_QUEUE_IN_MILLIS = "task_max_waiting_in_queue_millis";

   0340; COMBINING GRAVE TONE MARK
   0341; COMBINING ACUTE TONE MARK
   200E; LEFT-TO-RIGHT MARK
   200F; RIGHT-TO-LEFT MARK
   202A; LEFT-TO-RIGHT EMBEDDING
   202B; RIGHT-TO-LEFT EMBEDDING
   202C; POP DIRECTIONAL FORMATTING
   202D; LEFT-TO-RIGHT OVERRIDE
   202E; RIGHT-TO-LEFT OVERRIDE
   206A; INHIBIT SYMMETRIC SWAPPING
   206B; ACTIVATE SYMMETRIC SWAPPING
   206C; INHIBIT ARABIC FORM SHAPING
   206D; ACTIVATE ARABIC FORM SHAPING

    }
    assertNull(
        "The array element immediately following the end of the collection should be nulled",
        array[getNumElements()]);
    // array[getNumElements() + 1] might or might not have been nulled
  }

  @CollectionFeature.Require(KNOWN_ORDER)
  public void testToArray_oversizedArray_ordered() {
    E[] array = getSubjectGenerator().createArray(getNumElements() + 2);

    }
    assertNull(
        "The array element immediately following the end of the collection should be nulled",
        array[getNumElements()]);
    // array[getNumElements() + 1] might or might not have been nulled
  }

  @CollectionFeature.Require(KNOWN_ORDER)
  public void testToArray_oversizedArray_ordered() {
    E[] array = getSubjectGenerator().createArray(getNumElements() + 2);

		return err
	}
	for _, rt := range e.Right {
		err = rt.Right.aggregateRow(r, tableAlias)
		if err != nil {
			return err
		}
	}
	return nil
}

func (e *MultOp) aggregateRow(r Record, tableAlias string) error {
	err := e.Left.aggregateRow(r, tableAlias)
	if err != nil {
		return err
	}
	for _, rt := range e.Right {
		err = rt.Right.aggregateRow(r, tableAlias)
		if err != nil {

func (e *Operand) analyze(s *Select) (result qProp) {
	result.combine(e.Left.analyze(s))
	for _, r := range e.Right {
		result.combine(r.Right.analyze(s))
	}
	return
}

func (e *MultOp) analyze(s *Select) (result qProp) {
	result.combine(e.Left.analyze(s))
	for _, r := range e.Right {
		result.combine(r.Right.analyze(s))
	}
	return
}

func (e *UnaryTerm) analyze(s *Select) (result qProp) {