How to stream filepart to database (r2dbc postgres)?

The question says it. I could not find any information on streaming byte arrays to a postgresql database in spring using r2dbc, e.g. for a file upload.

I can store the bytes, by reading all bytes of a file like this:

@PostMapping("/upload")
suspend fun upload(
  @RequestPart("file") filePartMono: Mono<FilePart>
): User {
  val filePart = filePartMono.awaitFirstOrNull() ?: throw UploadException("Missing file part")
  var inputStream = filePart.content().awaitFirst().asInputStream()
  val bytes = coroutineScope {
    val bytesDeferred = async(Dispatchers.IO) {
      inputStream.readAllBytes()
    }
    bytesDeferred.await()
  }

  fileRepository.save(File(bytes));
}

But I would like to stream filePart.content() to the database if possible?