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From Patrick de Torcy <pdeto...@gmail.com>
Subject Re: how to know there are some columns in a row
Date Tue, 07 Jun 2011 22:30:16 GMT
But I want values in my columns... Imagine a cf with authors as keys. Each
author has written several books. So each row has columns with the title as
column names and the text of the book as value (ie a lot of data). If a user
wants to know the different books for an author, I'd like to be able to have
the column names without the values, then a user can pick a book name. In
this case I can retrieve the value from this column (and only for this one).
Of course, I could have an additionnal column which will manage the column
names (=titles), but it's not very efficient and could be source of
errors...
If you have a method to retrieve the number of columns of a row (without
their values),  I can't see why you couldn't retrieve the column names
(without their values). It's perharps harder than I think... But it would be
rather useful !

Thanks !

On Mon, Jun 6, 2011 at 2:08 AM, aaron morton <aaron@thelastpickle.com>wrote:

> You can create columns without values.
>
> Are you talking about reading them back through the API ?
>
> I would suggest looking at your data model to see if there is a better way
> to support your read patterns.
>
> Cheers
>
> -----------------
> Aaron Morton
> Freelance Cassandra Developer
> @aaronmorton
> http://www.thelastpickle.com
>
> On 6 Jun 2011, at 10:18, Patrick de Torcy wrote:
>
> It would be definetely useful to be able to have columns (or super columns)
> names WITHOUT their values. If these ones are pretty big or if there are a
> lot of columns, that would generate traffic not necessarily needed (if in
> the end you are just interrested by some column).
> Moreover it doesn't seem to be a feature too difficult to implement (well,
> I think...)
>
> Patrick
>
>
>

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