[ 
https://issues.apache.org/jira/browse/CASSANDRA-15938?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17165958#comment-17165958
 ] 

Caleb Rackliffe commented on CASSANDRA-15938:
---------------------------------------------

[~ifesdjeen] Just to make sure I'm not missing anything, aside from an extra 
newline, the 3.0 -> trunk patches are identical?

> Fix support for adding UDT fields to clustering keys
> ----------------------------------------------------
>
>                 Key: CASSANDRA-15938
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-15938
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Feature/UDT
>            Reporter: Alex Petrov
>            Assignee: Alex Petrov
>            Priority: Normal
>             Fix For: 3.0.x, 3.11.x, 4.0-beta
>
>
> Adding UDT fields to clustering keys is broken in all versions, however 
> slightly differently.
> In 4.0, there will be a brief moment while schema changes are propagated 
> during which we won’t be able to decode and compare byte sequences. 
> Unfortunately, it is unclear what we should do in such cases, since we can’t 
> just come up with a comparator, and we can’t ignore non-null trailing values, 
> since this will lead to cases where compare for tuples `a;1` and `a;2` would 
> return 0, effectively making them equal, and we don’t know how to compare 
> unknown trailing values. Probably we should reject such query since we can’t 
> sort correctly, but we should make the error message more descriptive than 
> just "Index 1 out of bounds for length 1”. The only problem is that we get 
> this exception only on flush right now, so data already propagates to the 
> node by that time.
> In 3.0, the problem is a bit worse than that, since in 3.0 we do not ignore 
> trailing nulls, so some of the values, written before `ALTER TYPE .. ADD` 
> become inaccessible. Both old values, and the new ones should always be 
> accessible.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org
For additional commands, e-mail: commits-h...@cassandra.apache.org

Reply via email to