On Mon, 2010-04-12 at 01:31 +0200, Philippe wrote:
> I have data that is two dimensional, time varying (think of a grid).
> At each
> cell of this grid,I store a binary array.
> My data model will be
>
> - single keyspace
> - key = {Y dimension}
> - super column family = {type of data represented in each cell}
> - super column = {time = week or month}
> - column ={X dimension}
> - value = { binary}
>
> Will I be able to retrieve all values from a rectangle from this grid
> in a single call to cassandra for given SCF and SC ?
If I understand what you're asking, a rectangle (identified by X and Y
coordinates for a time-frame), will boil down to a single column. There
are certainly no problems with retrieving a single sub-column from a
super column.
> Will the result associate each value with its key and column ?
The result will be a column that contains the binary value, which you
obtained by using key, column family, and super column name. So, yes.
> Does it matter if it's a single call performance wise ?
Yes, if for no other reason than it requires another round-trip across
the network.
--
Eric Evans
[email protected]
