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From aaron morton <aa...@thelastpickle.com>
Subject Re: Secondary indexes and cardinality
Date Mon, 13 Feb 2012 19:24:04 GMT
> Heard that indexing a field with high cardinality is not good. 
http://www.datastax.com/docs/0.7/data_model/secondary_indexes

> Will there be any performance improvement? Is this the way secondary indexes are maintained?
Updating secondary indexes requires a read and a write. 

> Also this makes me think – Will there be any lose if we have many rows in a CF say
10 million?
http://www.datastax.com/docs/0.7/data_model/cfs_as_indexes#indexes

Having 10 million columns in a row is not a problem by itself. It depends on how you want
to read things.

Cheers

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

On 14/02/2012, at 1:11 AM, Tiwari, Dushyant wrote:

> Hi Cassandra Users,
>  
> Heard that indexing a field with high cardinality is not good. If we create a CF to store
the index information like indexed field as key and the keys of original CF as cols in the
row. Will there be any performance improvement? Is this the way secondary indexes are maintained?
>  
> Also this makes me think – Will there be any lose if we have many rows in a CF say
10 million?
>  
> Thanks,
> Dushyant
>  
>    
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