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Robert Muir commented on SOLR-2338: ----------------------------------- {quote} ...but even if we don't do that, i suppose it's also conceivable that someone might have their own Similarity implementation that is expensive to instantiate (ie: maintains some big in memory data structures?) and might want to be able to declare one instance and then refer to it by name in many different fieldType declarations. {quote} I don't think this is really a use case we need to support: the purpose of Similarity today is to do term weighting, not to be a huge data-structure holder. While I know Mike's original patch went this way with LUCENE-2392 (e.g. norms), I'm not sure i like it being in Similarity in the future either. Otherwise concepts like lazy-loading norms and all this other stuff get pushed onto the sim, which is an awkward place (imagine if you have many fields). So, I think we shouldn't really design for abuses of the API. If there are other use cases for "named similarity" that have to do with term weighting, I'm interested. > improved per-field similarity integration into schema.xml > --------------------------------------------------------- > > Key: SOLR-2338 > URL: https://issues.apache.org/jira/browse/SOLR-2338 > Project: Solr > Issue Type: Improvement > Components: Schema and Analysis > Affects Versions: 4.0 > Reporter: Robert Muir > > Currently since LUCENE-2236, we can enable Similarity per-field, but in > schema.xml there is only a 'global' factory > for the SimilarityProvider. > In my opinion this is too low-level because to customize Similarity on a > per-field basis, you have to set your own > CustomSimilarityProvider with <similarity class=.../> and manage the > per-field mapping yourself in java code. > Instead I think it would be better if you just specify the Similarity in the > FieldType, like after <analyzer>. > As far as the example, one idea from LUCENE-1360 was to make a "short_text" > or "metadata_text" used by the > various metadata fields in the example that has better norm quantization for > its shortness... -- This message is automatically generated by JIRA. - For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org