Re: Fractal tree indexing

On 13 February 2013 16:48, Heikki Linnakangas <hlinnakangas(at)vmware(dot)com> wrote:
> On 13.02.2013 18:20, Tom Lane wrote:
>>
>> Heikki Linnakangas<hlinnakangas(at)vmware(dot)com> writes:
>>>
>>> The basic idea of a fractal tree index is to attach a buffer to every
>>> non-leaf page. On insertion, instead of descending all the way down to
>>> the correct leaf page, the new tuple is put on the buffer at the root
>>> page. When that buffer fills up, all the tuples in the buffer are
>>> cascaded down to the buffers on the next level pages. And recursively,
>>> whenever a buffer fills up at any level, it's flushed to the next level.
>>
>>
>> [ scratches head... ] What's "fractal" about that? Or is that just a
>> content-free marketing name for this technique?
>
>
> I'd call it out as a marketing name. I guess it's fractal in the sense that
> all levels of the tree can hold "leaf tuples" in the buffers; the structure
> looks the same no matter how deep you zoom, like a fractal.. But "Buffered"
> would be more appropriate IMO.

I hope for their sake there is more to it than that. It's hard to see
how buffering can be patented.

--
Simon Riggs http://www.2ndQuadrant.com/
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