code: func EncodeRowKeyWithHandle(tableID int64, handle int64) kv.Key {
  	buf := make([]byte, 0, recordRowKeyLen)
  	buf = appendTableRecordPrefix(buf, tableID)
  	buf = codec.EncodeInt(buf, handle)
  	return buf
  }
docs: // EncodeRowKeyWithHandle encodes the table id, row handle into a kv.Key