Retrieving the fields from the index is a costly operation. If your combined search returns a large number of hits then it can be too costly to get all the results form the index to check which field's caused that match. Therefore making separate searches, getting the hitcounts and top n-results can be faster(I think).
DIGY. -----Original Message----- From: Max Metral [mailto:[EMAIL PROTECTED] Sent: Thursday, March 06, 2008 1:25 PM To: lucene-net-dev@incubator.apache.org Subject: Multiple queries I have an app where I take a search string and split it into "tags" (i.e. categories) and regular text. I then use homegrown logic for tag matches, because it's faster/more efficient, and then correlate that with text results from Lucene. So the pathological example was a search for "atlantic fish". That's a restaurant name, but "fish" is also a tag, and it's not tagged with that so it's not matched. So what I would like to do is say "find the text (TermQuery), but also find a title match (using PhraseQuery)". That part is easy. The trick is I need to know for each text result which of those queries was responsible for the match. Which finally brings me to my question: Is it faster to do two searches, or one search and explain each result, or something entirely different? Thanks! --Max
