pkg database/sql/driver, type NamedValue struct, Ordinal int
pkg database/sql/driver, type NamedValue struct, Value Value
pkg database/sql/driver, type Pinger interface { Ping }
pkg database/sql/driver, type Pinger interface, Ping(context.Context) error
pkg database/sql/driver, type QueryerContext interface { QueryContext }

{"index":{"_index":"fess_config.scheduled_job","_id":"ping_es"}}

 * attempting to add new elements onto the queue and it is full. This queue orders elements FIFO
 * (first-in-first-out). This data structure is logically equivalent to a circular buffer (i.e.,
 * cyclic buffer or ring buffer).
 *
 * <p>An evicting queue must be configured with a maximum size. Each time an element is added to a
 * full queue, the queue automatically removes its head element. This is different from conventional

	if err := target.init(); err != nil {
		return false, err
	}
	return target.isActive()
}

func (target *MySQLTarget) isActive() (bool, error) {
	if err := target.db.Ping(); err != nil {
		if IsConnErr(err) {
			return false, store.ErrNotConnected
		}
		return false, err
	}
	return true, nil
}

                                  description: The ring/modulo hash load balancer
                                    implements consistent hashing to backend hosts.
                                  properties:
                                    minimumRingSize:
                                      description: The minimum number of virtual nodes
                                        to use for the hash ring.

    writer.write("Hi");
    writer.close();

    assertThrows(IOException.class, () -> writer.write(" Greg"));

    assertThrows(IOException.class, () -> writer.flush());

    // close()ing already closed writer is allowed
    writer.close();
  }

The benefit of raising an exception over `return`ing a value will be more evident in the section about Dependencies and Security.

In this example, when the client requests an item by an ID that doesn't exist, raise an exception with a status code of `404`:

```Python hl_lines="11"

		conn.Close()
		c.handleMsgWg.Done()
	}()

	c.connMu.Lock()
	connPingInterval := c.connPingInterval
	c.connMu.Unlock()
	ping := time.NewTicker(connPingInterval)
	pingFrame := message{
		Op:         OpPing,
		DeadlineMS: 5000,
	}

	defer ping.Stop()
	queue := make([][]byte, 0, maxMergeMessages)
	merged := make([]byte, 0, writeBufferSize)
	var queueSize int
	var buf bytes.Buffer

	biggerBufMin = 32 << 10

	// This is the maximum size of bigger buffers.
	biggerBufMax = maxBufferSize

	// If there is a queue, merge up to this many messages.
	maxMergeMessages = 30

	// clientPingInterval will ping the remote handler every 15 seconds.
	// Clients disconnect when we exceed 2 intervals.
	clientPingInterval = 15 * time.Second

	// Deadline for single (non-streaming) requests to complete.

	if m.outBlock == nil {
		// Closed
		return
	}
	select {
	case m.outBlock <- struct{}{}:
	default:
		gridLogIf(m.ctx, errors.New("output unblocked overflow"))
	}
}

func (m *muxServer) ping(seq uint32) pongMsg {
	if !m.checkSeq(seq) {
		msg := fmt.Sprintf("receive sequence number mismatch. want %d, got %d", m.RecvSeq, seq)
		return pongMsg{Err: &msg}
	}
	select {
	case <-m.ctx.Done():