2. Add events as a JSON array, with one event per element.

3. Click**Run** to preview the batch handler with the specified events.

The editor displays logs and request traces from the batch handler.

]

Afterreceiving theresponse from the`onBatch` handler, Segment only retries**event_4** and**event_5**.

For example, afterreceiving theresponses above from the`onBatch` handler, Segment only retries**event_4** and**event_5**.

| Error Type| Result|

| ----------------------| -------|

Batch handlers are an extension of insert functions. When you define an`onBatch` handler alongside the handler functions for single events (for example,`onTrack` or`onIdentity`), you're telling Segment that the insert function can accept and handle batches of events.

The handler function receives an array of events. The events can be of any supported type and a single batch may contain more than one event type. Handler functions can also receive function settings. Here is an example of what a batch can look like:

By default, Functions waits up to 10 seconds to form a batch of 20 events. You can increase the number of events included in each batch (up to 400 events per batch) by contacting[Segment support](https://segment.com/help/contact/){:target="_blank"}. Segment recommends users who wish to include fewer than 20 events per batch use destination functions without the`onBatch` handler.

By default, Functions waits up to 10 seconds to form a batch of 20 events. You can increase the number of events included in each batch (up to 400 events per batch) by contacting[Segment support](https://segment.com/help/contact/){:target="_blank"}. Segment recommends users who wish to include fewer than 20 events per batch use destinationinsertfunctions without the`onBatch` handler.

2. Add events as a JSON array, with one event per element.

3. Click**Run** to preview the batch handler with the specified events.

The editor displays logs and request traces from the batch handler.

]

Afterreceiving theresponse from the`onBatch` handler, Segment only retries**event_4** and**event_5**.

For example, afterreceiving theresponses above from the`onBatch` handler, Segment only retries**event_4** and**event_5**.

| Error Type| Result|

| ----------------------| -------|