docs: public void writeExecute(String portal, int rowCount) {
      ensureBuffer();
      int pos = out.writerIndex();
      out.writeByte(EXECUTE);
      out.writeInt(0);
      if (portal != null) {
        out.writeCharSequence(portal, StandardCharsets.UTF_8);
      }
      out.writeByte(0);
      out.writeInt(rowCount); // Zero denotes "no limit" maybe for ReadStream<Row>
      out.setInt(pos + 1, out.writerIndex() - pos - 1);
    }