cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From aaron morton <aa...@thelastpickle.com>
Subject Re: Querying for rows without a particular column
Date Tue, 14 Feb 2012 09:23:05 GMT
I would try to come up with a different model. Expired columns are essentially deleted columns.


Can you create a manual secondary index that uses the time the column will have expired at.

e.g. 
row: <date>
column: <expiry_time:row_key:column>

When you write the row with the expiry time also write a column here that says this is when
it will expire. 

Not convinced it's a great idea but it's one option. 

Cheers

-----------------
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com

On 14/02/2012, at 9:12 PM, R. Verlangen wrote:

> One option might be to maintain an index containing the keys of the rows. The index would
then have the same TTL as the row itself so when you iterate over the index columns you'll
find exactly the same results. Although I'm not really sure whether this is the best option.
> 
> Another might be to use Hadoop to find your results with a map/reduce task.
> 
> 2012/2/13 Asankha C. Perera <asankha@apache.org>
> Hi All
> 
> I am using expiring columns in my column family, and need to search for the rows where
a particular column expired (and no longer exists).. I am using Hector client. How can I make
a query to find the rows of my interest?
> 
> thanks
> asankha
> 
> -- 
> Asankha C. Perera
> AdroitLogic, http://adroitlogic.org
> 
> http://esbmagic.blogspot.com
> 
> 
> 
> 
> 


Mime
View raw message