Trie has a custom parser that can load the FieldCache for sorting. Its basically a built in type now, that supports fieldcache, sorting, stored fields, etc.
On Sat, Jul 4, 2009 at 3:27 PM, Chris Hostetter <hossman_luc...@fucit.org>wrote: > > : My data are library call numbers, normalized to be comparable, resulting > in > : (maximum) 21-character strings of the form "RK 052180H359~999~999" > : > : Now, these are fine -- they work for sorting and ranges and the whole > thing, > : but right now I can't use them because I've got two or three for each of > my > : 6M documents and on a 32-bit machine I run out of heap. > : > : Another option would be to turn them into longs (using roughly 56 bits of > : the 64 bit space) and use a trie type. Is there any sort of a win > involved > : there? > > I don't think Trie fields can be used for sorting (because they result in > multiple terms per doc) but i could be wrong about that, smarter people > then me may have done something cool with the TreiField that i'm not aware > of. > > As a general rule: if you have character data that fits a rigid enough set > of constraints that you can encode any legal value into a single > numberic value (either int, or long) such that they still sort properly, > sorting on those encoded values is going to be more memory efficient (and > probably just as fast) as sorting on the string values. > > > -Hoss > > -- -- - Mark http://www.lucidimagination.com
