Hello, I'm trying to implement automatic document classification and store the classified attributes as an additional field in Solr document. Then the search goes against that field like q=classified_category:xyz. The document classification is currently implemented as an UpdateRequestProcessor and works quite well. The only problem: for each change in the classification algorithm every document has to be re-indexed which, of course, makes tests and experimentation difficult and binds resources (other than Solr) for several hours.
So, my idea would be to store classified attributes in a meta-index and search over the main and meta indexes simultaneously. For example: main index has got fields like color and meta index has got classified_category. The query "q=classified_category:xyz AND color:black" should be then split over the main and meta index. This way, the classification could run on Solr over the main index and store classified fields in the meta index so that only Solr resources are bound. Has anybody already done something like that? It's a little bit like sharding but different in that each shard would process its part of the query and live in the same Solr instance. Regards, Valeriy
