search for: op_and_not

Hi, I have read the concurrency webpage from the Xapian documentation: http://getting-started-with-xapian.readthedocs.io/en/latest/concepts/concurrency.html But it is still not clear to me how to ensure thread-safety when using libxapian (C++ API). Usually when doing multi-threading many threads can read the same variable concurrently without locking provided none of the threads modifies the

...nguage Processing is not a new thing and there has been lot of work done that yield inconsistent results. What I am trying to point out is that we need start to think about using natural language processing when placing infrastructure for Xapian. So far we have the following OP_AND, OP_AND_MAYBE, OP_AND_NOT, OP_ELITE_SET, OP_FILTER, OP_NEAR, OP_OR, OP_PHRASE, OP_VALUE_RANGE, OP_XOR search operators and we could add one more OP_NLP. What we can do now is to implement OP_NLP to tagged nouns, adjectives, adverbs, punctuations, foreign words etc. Calculate relation between them and assign boost value to...

...ueries OP_OR is the example used in the description, but the ticket isn't only about OP_OR - note "OP_OR, *etc*" in the description, the title says "non-leaf subqueries", and other operators are explicitly discussed: * OP_AND: https://trac.xapian.org/ticket/508#comment:8 * OP_AND_NOT: https://trac.xapian.org/ticket/508#comment:11 I've added a note about OP_NEAR/OP_PHRASE. > > The code I pushed before wouldn't handle an OR of more than two things, > > so you couldn't do a 3+-way stem expansion: > > > > (text OR texts) NEAR (search O...

Hi all, I am a new user to Xapian, and now we met such problem. In our case, a document has many attributes which is boolean value, for example( A, B, C ) , and our search query will use certain filter logic ( A == true and B == false ..) to combine with other search logic. We use MatchDecider to implement the filter logic, and now we met some performance problem, because our self-defined

...on fault (core dumped). It looks like some pointers are double freed. This is the function that we use to create xapian-query. std::shared_ptr<Xapian::Query> constructQuery() { Xapian::Query black_list("BLt1"); return std::make_shared<Xapian::Query>(Xapian::Query::OP_AND_NOT, Xapian::Query::MatchAll, black_list); } I have wrote a demo to reproduce our problems, you can click this link for the detail. https://github.com/xiangqianzsh/xapian_leaning/tree/master/matchall_coredump How we solve this problems?

Olly Betts writes: > On Thu, Jan 12, 2017 at 07:53:21PM +0100, Jean-Francois Dockes wrote: > > > Recoll also supports multi-word synonyms which could potentially > > generate PHRASE subqueries inside NEAR queries, but this > > understandably already did not work with 1.2, so the multi-word > > expansions are only used when proximity is not involved (by the way,