presto-main/src/main/java/io/prestosql/operator/DeleteOperator.java/DeleteOperator/close
class DeleteOperator:    @Override
    public void close()
    {
        if (!closed) {
            closed = true;
            if (finishFuture != null) {
                finishFuture.cancel(true);
            }
            else {
                pageSource.get().ifPresent(UpdatablePageSource::abort);
            }
        }
    }