Please note this is only a concern when using the`create` operation. You can use the`upsert` operation instead to avoid duplicates if`upsert` meets your needs.

When**Use Salesforce Bulk API** is enabled for your mapping, events are sent to[Salesforce’s Bulk API 2.0](https://developer.salesforce.com/docs/atlas.en-us.api_asynch.meta/api_asynch/asynch_api_intro.htm){:target="_blank"} rather than their streaming REST API. If enabled, Segment will collect events into batches of 1000 before sending to Salesforce. Bulk support can be used for the`upsert` or`update` operations only.

When**Use Salesforce Bulk API** is enabled for your mapping, events are sent to[Salesforce’s Bulk API 2.0](https://developer.salesforce.com/docs/atlas.en-us.api_asynch.meta/api_asynch/asynch_api_intro.htm){:target="_blank"} rather than their streaming REST API. If enabled, Segment will collect events into batches ofup to1000 before sending to Salesforce. Bulk support can be used for the`upsert` or`update` operations only.

For bulk`update`, if a record in a batch is missing a Bulk Update Record ID, Segment will still send it to Salesforce. Salesforce will reject the individual record because it will be unable to find a record to update. Other records in the batch that are valid will still be processed. Please note that Segment's Event Delivery tab will show the entire batch as successful as Segment cannot currently break down Event Delivery stats into individual failed/passed events.