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From Eric Evans <eev...@rackspace.com>
Subject Re: Two dimensional matrices
Date Mon, 12 Apr 2010 22:38:34 GMT
On Tue, 2010-04-13 at 00:23 +0200, Philippe wrote:
> > Alright, so assuming we're looking for a slice of the grid against a
> > given time-frame, that would look something like:
> >
> > get_range_slice(
> >    keyspaceName,
> >    ColumnParent(CFname, timeFrame),
> >    SlicePredicate(
> >        slice_range=SliceRange(xstart, xend, false, colCount)
> >    ),
> >    ystart,
> >    yend,
> >    rowCount,
> >    consistencyLevel,
> > )
> >
> > Does that help?
> >
> Yes it confirms my understanding, thanks.
> 
> However, you are also saying there is no way to also take into account
> the "timeFrame" supercolumn in the same API call ? IE, it is not
> possible to get back a data structure keyed by
> 'key,supercolumn,column' hence y,x and timeframe which I can then
> process to my heart's delight ? 

If you're talking about constructing predicates to slice on both time
*and* X coordinate, then no. You can omit the super column name from the
ColumnParent and return a slice of super columns (by time period)
complete with all contained sub-columns, but you can't have it both
ways, no.

-- 
Eric Evans
eevans@rackspace.com


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