The bonus you're talking about here, how do I apply that?

 For example, my columns are in the form of number.id such as 4.steve, 4.greg, 
5.steve, 5.george. Is there a way to query a slice of numbers with a list of 
ids? As in, I want all the columns with numbers between 4 and 10 which have ids 
steve or greg.

 Cheers,
 Steve

-----Original Message-----
From: Jeremiah Jordan [mailto:jeremiah.jor...@morningstar.com] 
Sent: Tuesday, January 03, 2012 3:12 PM
To: user@cassandra.apache.org
Cc: Asil Klin
Subject: Re: Replacing supercolumns with composite columns; Getting the 
equivalent of retrieving a list of supercolumns by name

The main issue with replacing super columns with composite columns right now is 
that if you don't know all your sub-column names you can't select multiple 
"super columns" worth of data in the same query without getting extra stuff.  
You have to use a slice to get all subcolumns of a given super column, and you 
can't have disjoint slices, so if you want two super columns full, you have to 
get all the other stuff that is in between them, or make two queries.
If you know what all of the sub-column names are you can ask for all of the 
super/sub column pairs for all of the super columns you want and not get extra 
data.

If you don't need to pull multiple super columns at a time with slices like 
that, then there isn't really an issue.

A bonus of using composite keys like this, is that if there is a specific sub 
column you want from multiple super columns, you can pull all those out with a 
single multiget and you don't have to pull the rest of the columns...

So there are pros and cons...

-Jeremiah


On 01/03/2012 01:58 PM, Asil Klin wrote:
> I have a super columns family which I always use to retrieve a list of 
> supercolumns(with all subcolumns) by name. I am looking forward to 
> replace all SuperColumns in my schema with the composite columns.
>
> How could I design schema so that I could do the equivalent of 
> retrieving a list of supercolumns by name, in case of using composite 
> columns.
>
> (As of now I thought of using the supercolumn name as the first 
> component of the composite name and the subcolumn name as 2nd 
> component of composite name.)

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