[ 
https://issues.apache.org/jira/browse/CASSANDRA-3929?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13593488#comment-13593488
 ] 

Ahmet AKYOL commented on CASSANDRA-3929:
----------------------------------------

I see [~slebresne]'s point and even without knowing C* internals, it really 
sounds like an impossible task to do. The real problem here is, during 
compaction, nodes have to deal with many rows; it's like a thread 
synchronization nightmare on node level(a.k.a. distributed systems:) ). So why 
not give responsibility to users and provide something like that :

{code}
delete from recentuseractivities where userid=1 AFTER COLUMN [50]; 
{code} 

users may add this statement after every insert in a batch or they can find a 
way to call it less. It should skip tombstones and may not throw an exception 
for small sizes of course... 
since it's row based, it seems doable to me.

or you may add this kind of feature to lists:

{code}
DELETE top_places [>50] FROM users WHERE user_id = 'frodo';
{code} 
something like [>N] could be added ...

just my two cents, no intention to interrupt your development process 
                
> Support row size limits
> -----------------------
>
>                 Key: CASSANDRA-3929
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3929
>             Project: Cassandra
>          Issue Type: New Feature
>          Components: Core
>            Reporter: Jonathan Ellis
>            Assignee: Dave Brosius
>            Priority: Minor
>              Labels: ponies
>             Fix For: 2.0
>
>         Attachments: 3929_b.txt, 3929_c.txt, 3929_d.txt, 3929_e.txt, 
> 3929_f.txt, 3929_g_tests.txt, 3929_g.txt, 3929.txt
>
>
> We currently support expiring columns by time-to-live; we've also had 
> requests for keeping the most recent N columns in a row.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Reply via email to