Xapian discuss - Jul 2013 - Indexing, searching and sorting signed integers

Hi,

for a project we need to index, search and sort by negative integers
(years b.c.) in Xapian. Is this possible?

I already tried to index the negative integers including a search
prefix with add_term.

I have theses terms in my index

X7-58 X7-59 X7-60 

But the query parser seems to ignores the dash when searching:

2013/07/05 15:57:53 DEBUG> Xapian.pm:812
OpenBib::Search::Backend::Xapian::parse_query - Xapian-Querystring: year:-59 -
Xapian-Filterstring:
2013/07/05 15:57:53 DEBUG> Xapian.pm:292
OpenBib::Search::Backend::Xapian::search - Internal Xapian Query:
Xapian::Query(X759:(pos=1))

I got the Internal Xapian Query with $enq->get_query()->get_description();

For the actual enquiry I used

my $enq       =
$dbh->enquire($self->{qp}->parse_query($fullquerystring,FLAG_WILDCARD|FLAG_BOOLEAN|FLAG_PHRASE));

with year:-59 as $fullquerystring and X7 as the search prefix for year.

I would have expected X7-59 for the internal query term... And of
course I only got results for a positive term 59 ;-)

Regards,

Oliver

-- 
Universitaet zu Koeln :: Universitaets- und Stadtbibliothek
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On Fri, Jul 05, 2013 at 04:27:43PM +0200, Oliver Flimm
wrote:
> with year:-59 as $fullquerystring and X7 as the search prefix for year.
> 
> I would have expected X7-59 for the internal query term... And of
> course I only got results for a positive term 59 ;-)
It works if you set year as a boolean prefix, which is what you almost
certainly want to do anyway:

$ examples/quest -byear:X7 "rome year:-59"
Parsed Query: Query((Zrome at 1 FILTER X7-59))

Cheers,
    Olly