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https://issues.apache.org/jira/browse/PHOENIX-3534?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15963590#comment-15963590
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churro morales commented on PHOENIX-3534:
-----------------------------------------

For the above approach, it seems like we will need to add (timestamp) to 
PColumn to get this information, otherwise we will end up doing lots of extra 
point gets and it looks like it wont be cached either.  [~jamestaylor] what do 
you think?

> Support multi region SYSTEM.CATALOG table
> -----------------------------------------
>
>                 Key: PHOENIX-3534
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-3534
>             Project: Phoenix
>          Issue Type: Bug
>            Reporter: James Taylor
>            Assignee: churro morales
>
> Currently Phoenix requires that the SYSTEM.CATALOG table is single region 
> based on the server-side row locks being held for operations that impact a 
> table and all of it's views. For example, adding/removing a column from a 
> base table pushes this change to all views.
> As an alternative to making the SYSTEM.CATALOG transactional (PHOENIX-2431), 
> when a new table is created we can do a lazy cleanup  of any rows that may be 
> left over from a failed DDL call (kudos to [~lhofhansl] for coming up with 
> this idea). To implement this efficiently, we'd need to also do PHOENIX-2051 
> so that we can efficiently find derived views.
> The implementation would rely on an optimistic concurrency model based on 
> checking our sequence numbers for each table/view before/after updating. Each 
> table/view row would be individually locked for their change (metadata for a 
> view or table cannot span regions due to our split policy), with the sequence 
> number being incremented under lock and then returned to the client.



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