MongoDB\UpdateResult::getUpsertedId()
Definition
Return Values
The ID (i.e. _id field value) of the upserted document. If no document was upserted, null will be returned.
If the document had an ID prior to upserting (i.e. the server did not need to generate an ID), this will contain its _id field value. Any server-generated ID will be a
Errors/Exceptions
MongoDB\Exception\BadMethodCallException if this method is called and the write operation used an unacknowledged write concern.