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From graham sanderson <gra...@vast.com>
Subject Re: Delete By Partition Key Implementation
Date Fri, 08 Aug 2014 21:28:29 GMT
A deletion of an entire row is a single row tombstone, and yes there are range tombstones for
marking deletion of a range of columns also

On Aug 8, 2014, at 2:17 PM, Kevin Burton <burton@spinn3r.com> wrote:

> This is a good question.. I'd love to find out the answer.  Seems like a tombstone with
prefixes for the keys would work well.
> 
> Also, can't any key prefixes work in theory?
> 
> 
> On Thu, Aug 7, 2014 at 8:33 AM, DuyHai Doan <doanduyhai@gmail.com> wrote:
> Hello all
> 
>  Usually, when using DELETE in CQL3 on some fields, C* creates tombstone columns for
those fields.
> 
>  Now if I delete a whole PARTITION (delete from MyTable where partitionKey=...), what
will C* do ? Will it create as many tombstones as there are physical columns on this partition
or will it just mark this partition as "deleted" (Row Key deletion marker) ?
> 
>  On a side note, if I insert a bunch of physical columns in one partition with the SAME
ttl value, after a while they will appear as expired, would C* need to scan the whole partition
on disk to see which columns to expire or could it see that the whole partition is indeed
expired thanks to meta data/ Partition key cache kept in memory ?  I was thinking about the
estimate histograms for TTL but I don't know in detail how it work
> 
>  Regards
> 
>  Duy Hai  DOAN
> 
> 
> 
> 
> -- 
> 
> Founder/CEO Spinn3r.com
> Location: San Francisco, CA
> blog: http://burtonator.wordpress.com
> … or check out my Google+ profile
> 
> 


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