[elephant-devel] Collection paging

[Mariano Montone]

Thanks Ian for your long answer :) :

2007/10/3, Ian S Eslick <eslick at csail.mit.edu>:
>
>  When you say indexes are not sequential, do you mean UIDs are not
> sequentially allocated?  I think there is a BDB sequence issue that I've
> never worried about that jumps to the nearest 100 when you reconnect.
>

Yes, it seems to be jumping by 100.

  However, if you create anything other than a user object, you will also
> have gaps in the UID sequence so that's a fundamental issue.  Don't assume
> anything about UIDs other than the fact that they are unique.
>

Ok

The first idea that occurs to me is to drop the idea of using an indexed
> class or standalone btrees and just build a red-black tree using object
> slots (you can inherit from a base class that implements the RB tree
> functionality).  This simultaneously solves the count problem and the access
> element # N problem.
>

Interesting. I'll have a look at them.

Now there is a problem that you'll need one of these for each sorted order
> which for a list sorted many different ways is a problem.  Anyone know how
> SQL query systems implement this?
>

No idea.

Just remember that premature optimization is one of the four horseman of the
> apocalypse for the effective programmer.
>

Thank you again for your answer and your advice.

Mariano
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