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From "Uwe Schindler" <...@thetaphi.de>
Subject RE: TrieRange
Date Sat, 07 Feb 2009 17:29:17 GMT
Hi Yonik,

> On Sat, Feb 7, 2009 at 6:04 AM, Uwe Schindler <uwe@thetaphi.de> wrote:
> > The field names could be changed, sure, the small performance
> optimization
> > is in TrieRangeFilter: The splitting of the range is done in a way, to
> not
> > seek back and forward in the Term list, just in forward direction. This
> is
> > only possible if the helper field is ordered *after* the original one.
> 
> This should not matter unless the terms are near each other.
> That won't be the case with two different fields in a sufficiently sized
> index.

This is only a minimal optimization, suitable for very large indexes. The
problem is: if you have many terms in highest precission (a lot of different
double values), seeking is more costly if you jump from higher to lower
precisions. But as I noted, there is no problem for the code, the names of
the fields do not matter. The only optimization is if the helper field comes
before or after the main one.

Uwe


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