Hi Cliff, Thanks for bringing this up! AFAIK, this wouldn't be a long-term blocker. I've just opened a JIRA to track this [1].
As explained in the JIRA ticket, the main reason this is disallowed in the initial support for state schema evolution was due to how migration was implemented in the RocksDB state backend. Technically speaking, enabling this in the future is definitely possible. Cheers, Gordon [1] https://issues.apache.org/jira/browse/FLINK-11947 On Mon, Mar 18, 2019 at 11:20 AM Cliff Resnick <cre...@gmail.com> wrote: > After trying out state migration in 1.8 rc2 I ran into this hard stop > below. The comment does not give an indication why rocksdb map state cannot > be migrated, and I'm wondering what the status is, since we do need this > functionality and would like to know if this is a long-term blocker or not. > Anyone know? > > > https://github.com/apache/flink/blob/953a5ffcbdae4115f7d525f310723cf8770779df/flink-state-backends/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/RocksDBKeyedStateBackend.java#L542 >
