问题
I recently found out that Cassandra 3.0.0 and PrestoDB don't play well together.
I have a lot of data loaded into Cassandra 3.0 and I wouldn't like to rebuild the whole thing. Is there a safe way to downgrade to 2.x temporarily until Presto is updated, so then I can come back to 3.0?
I know downgrading is not officially supported, but I'm wondering whether more experienced S.O. Cassandra users could point me in the right direction here. I assume the answer will be "don't try it", but who knows, maybe there's a way. Thanks in advance.
Update 2016-11-05 : Using version 0.147 and newer of PrestoDB and this issue has been solved. In the end I did not need to downgrade Cassandra in order to use PrestoDB. Thanks for your replies.
回答1:
If you've started with 3.0, the only way I can think of is to export all your data then reimport it. The storage format has massively changed and 2.x can't read the 3.0 tables.
Unfortunately sstable2json was removed in 3.0, so you'll probably need to export it all manually then import into a previous version.
来源：https://stackoverflow.com/questions/34634932/how-to-downgrade-cassandra-3-0-0-2-x