Github user StefanRRichter commented on the issue:
https://github.com/apache/flink/pull/5979
@sihuazhou I wonder why you would chose iterator + batched write over
simply calling `db.deleteRange(...)` where start key is
`serializeCurrentKeyAndNamespace()` and end key is increasing the last byte of
the start key by one. That seems like an even better idea to me, what do you
think?---
