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From Erik Holstad <erikhols...@gmail.com>
Subject Re: Reason for not allowing null values for in Column
Date Mon, 08 Mar 2010 18:31:57 GMT
On Mon, Mar 8, 2010 at 10:14 AM, Jonathan Ellis <jbellis@gmail.com> wrote:

> On Mon, Mar 8, 2010 at 12:07 PM, Erik Holstad <erikholstad@gmail.com>
> wrote:
> > So why is it again that the value field in the Column cannot be null if
> it
> > is not the
> > value field in the map, but just a part of the value field?
>
> Because without a compelling reason to allow nulls, the best policy is
> not to do so.
>
> This for me is about memory usage, I guess, so I was just curious if there
was a good reason
for using more than needed and I guess best policy is a reason for that.

> All of this makes total sense, I'm wondering about use cases where you
> want
> > to
> > get an empty row when you don't know if it has been deleted or not.
>
> If you're saying, "I understand that doing X would be Really
> Inefficient, but I want you to do it anyway because of some use case
> that nobody actually needs so far," then I think you have your answer.
>
> If that is not what you are asking then you'll need to give me a
> concrete example because I don't understand the question.
>
> Well, I cannot say that I understand all of this, since I'm not getting it
:)
But for me when you do a range query you want to know what data that you
have to work
with in those rows and usually not too interested in the empty ones. And the
reason for not
returning empty ones would be to save IO.


> -Jonathan
>



-- 
Regards Erik

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