On Nov 14, 2007 6:44 AM, Mike Klaas <[EMAIL PROTECTED]> wrote:
>
> An implementation might look like:
>
> DocList superlist;
> int facetDocLimit = params.getInt(DMP.FACET_DOCLIMIT, -1);
> if(facetDocLimit > 0 && facetDocLimit != req.getLimit()) {
> superlist = s.getDocList(query, restrictions,
> SolrPluginUtils.getSort(req),
> req.getStart(), facetDocLimit,
> flags);
> results.docSet = SearcherUtils.getDocSetFromDocList
> (superlist, s);
> results.docList = superlist.subset(0, req.getLimit());
> } else {
>
> Where getDocSetFromDocList() uses DocSetHitCollector to build a DocSet.
>
> To answer the performance question: There is a gain to be had when
> doing lots of faceting on huge indices, if N is low (say, 500-1000).
> One problem with the implementation above is that it stymies the
> query caching in SolrIndexSearcher (since the generated DocList is >
> the cache upper bound).
>
> -Mike
Thanks Mike, that looks like a good place to start. While I really
can't think of any practical use for limiting the size of DocSet other
than simple faceting, the new search component architecture make it a
little more difficult to confine any implementation to only the facet
component (unless there is an efficient way to obtain a subset of a
DocSet, which there doesn't seem to be). I'm also aware of the query
caching issues arising from SolrIndexSearcher however if N is
sufficiently low this (hopefully) shouldn't be too much of a problem.
I can't find either the SearcherUtils class nor any reference to a
getDocSetFromDocList() method in svn trunk, is this deprecated or
custom-build code?
-Piete
