Hi, this is because the list state is intended to be append only. The underlying reason is that this allows certain optimizations in the underlying datastructures. For example, a list state for the RocksDB backend can make use of RocksDB’s merge operator and does not require a full rewrite to the DB on appends.
If you need to have a list that supports this, you could use a value state of type list or use a map state where you map from list-index -> element. Best, Stefan > Am 17.08.2017 um 06:07 schrieb yunfan123 <yunfanfight...@foxmail.com>: > > If I want to update the list. > I have to do two steps: > listState.clear() > for (Element e : myList) { > listState.add(e); > } > > Why not I update the state by: > listState.update(myList) ? > > > > -- > View this message in context: > http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/Why-ListState-of-flink-don-t-support-update-tp14957.html > Sent from the Apache Flink User Mailing List archive. mailing list archive at > Nabble.com.