I need to facet inside n documents which are selected like
... ORDER BY something DESC LIMIT 100
Is that possible with Solr? How?
AFAIK no, that's not supported / implemented. Facets aren't really meant to be "stats" but a guidance to the end-user. Picture yourself browsing a faceted interface and seeing facets change whenever you change sort order or paging. Faceted browsing would be useless if it worked like that.
I think this would be a nice feature for the StatsComponent though.