cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Adi <adi.pan...@gmail.com>
Subject Re: ballpark low cardinality range for secondary indexes
Date Fri, 08 Apr 2011 20:47:48 GMT
Thanks for the suggestions Ed.  Your blog post is quite helpful in deciding
on and implementing CF inverted indexes.
Our data definitely leans towards external CF - has high cardinality(1000s
for one column, millions for another), multiple columns need to be indexed,
needs sorted order.
Hope that amazon paper has some good tips on solving the transactional
gotcha :-)

-Adi

On Fri, Apr 8, 2011 at 3:49 PM, Ed Anuff <ed@anuff.com> wrote:

> If you're just indexing on a single column value and the values have
> low cardinality in, say, the 10's - I'd have a wide row for each
> cardinal value that contained the set of keys for rows that contained
> that value.  For higher levels of cardinality or if you're indexing on
> multiple columns, there are tradeoffs for secondary indexes versus CF
> inverted indexes that are based on atomicity of updates, complexity of
> queries, and whether you need to get results in sorted order.
> Secondary indexes are usually the best starting point since they're
> easy to set up and use, versus CF inverted indexes, where you'll need
> to manage all that yourself.  Some of the client libraries make it
> easier to build CF inverted indexes, Hector is going to soon have some
> capabilities for JPA users leveraging the new composite column types
> to do this.  I wrote up a blog post a while back talking about
> indexing approaches at
> http://www.anuff.com/2011/02/indexing-in-cassandra.html that you might
> find useful, although it sounds like you're already familiar with the
> concepts
>
> Ed
>
> On Fri, Apr 8, 2011 at 7:53 AM, Adi <adi.pandit@gmail.com> wrote:
> > I am trying to decide whether to use secondary indexes or use an inverted
> > index column family for a use case. Is there any suggested ballpark range
> > for low cardinality for which secondary indexes are suitable.
> > Meaning at what range should  using a secondary index be ruled in or out:
> > cardinality of tens, hundreds, thousands,millions?
> > I am not looking for any tested numbers a general suggestion/best
> practice
> > recommendation will suffice.
> >
> > Thanks.
> >
> > -Adi
> >
> >
>

Mime
View raw message