Ron <[EMAIL PROTECTED]> writes:
> At 07:23 PM 1/20/2006, Tom Lane wrote:
>> Well, we're trying to split an index page that's gotten full into
>> two index pages, preferably with approximately equal numbers of items in
>> each new page (this isn't a hard requirement though).
> Maybe we are over thinking this. What happens if we do the obvious
> and just make a new page and move the "last" n/2 items on the full
> page to the new page?
Search performance will go to hell in a handbasket :-(. We have to make
at least some effort to split the page in a way that will allow searches
to visit only one of the two child pages rather than both.
It's certainly true though that finding the furthest pair is not a
necessary component of that. It's reasonable if you try to visualize
the problem in 2D or 3D, but I'm not sure that that geometric intuition
holds up in such a high-dimensional space as we have here.
regards, tom lane
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