[Xapian-discuss] what does get_eset do?; searching by relevance and value; what is the scope of an enquire object?;

[Jason W. Solinsky]

I've been playing around with Xapian for a few weeks now and I'm very
impressed. Now I'm planning on applying it to some more difficult searching
tasks, and I'm hoping that somebody here can answer my questions concerning
its use.


1. What is Enquire.get_eset supposed to do?

Does it return terms which are:

a. related to documents that would be returned by the current query?
b. related to documents that are in the input RSet?
c. related to documents that are in the input RSet AND would be returned by
the current query
d. something else?



2. What is the preferred way of combining a search by relevance and a search
by value? Suppose I am running a query that returns thousands of results and
I want to identify the best 100 documents by some combination of document
value and relevance to the query. Is the preferred way to first find all the
desired results, and then filter through them by value, or is there some way
of improving efficiency by combining both into a single step?



3. How does Query::OP_ELITE_SET work?



4. What is the intended scope of an Enquire object?

Is there any particular performance advantage or robustness penalty to using
a single enquire object across multiple calls to get_eset and get_mset?



5. Finally, is there a particular place in the documentation that I should
be looking to find answers to questions such as these?

Thanks in advance,


JWS