cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From David Boxenhorn <>
Subject Re: Is SuperColumn necessary?
Date Sun, 09 May 2010 06:30:17 GMT
Guys, this is beginning to sound like MUMPS!

In MUMPS, all variables are sparse, multidimensional arrays, which can be
stored to disk.

It is an arcane, and archaic, language (does anyone but me remember it?),
but it has been used successfully for years. Maybe we can learn something
from it.

I like the terminology of sparse multidimensional arrays very much - it
really clarifies my thinking. A column family would just be a variable.

On Fri, May 7, 2010 at 7:06 PM, Ed Anuff <> wrote:

> On Thu, May 6, 2010 at 11:10 PM, Mike Malone <> wrote:
>> The upshot is, the Cassandra data model would go from being "it's a nested
>> dictionary, just kidding no it's not!" to being "it's a nested dictionary,
>> for serious." Again, these are all just ideas... but I think this
>> simplified
>> data model would allow you to express pretty much any query in a graph of
>> simple primitives like Predicates, Filters, Aggregations, Transformations,
>> etc. The indexes would allow you to cheat when evaluating certain types of
>> queries - if you get a SlicePredicate on an indexed "thingy" you don't
>> have
>> to enumerate the entire set of "sub-thingies" for example.
> This would be my dream implementation. I'm working an an application that
> needs that sort of capability.  SuperColumns lead you to thinking that
> should be done in the cassandra tier but then fall short, so my thought was
> that I was just going to do everything that was in Cassandra as regular
> columnfamilies and columns using composite keys and composite column names
> ala the code I shared above, and then implement the n-level hierarchy in the
> app tier.  It looks like your suggestion is to take it in the other
> direction and make it part of the fundamental data model, which would be
> very useful if it could be made to work without big tradeoffs.

View raw message