NAME¶

Search::Xapian::Enquire - Make queries against a database

DESCRIPTION¶

This class provides an interface to the information retrieval system for the purpose of searching.

METHODS¶

new

set_query

takes either a ready made Search::Xapian::Query or a scalar containing a query, which in that case will be passed to Search::Xapian::Query's constructor, together with any other passed arguments.

set_query_object <query>

get_query

matches <start> <size> [<check_at_least>]

Takes the start element, and maximum number of elements (and optionally the minimum number of matches to check), and returns an array tied to Search::Xapian::MSet::Tied.

get_matching_terms_begin

Returns a Search::Xapian::TermIterator, pointing to the start of the stream.

get_matching_terms_end

Returns a Search::Xapian::TermIterator, pointing to the end of the stream.

set_collapse_key <collapse_key>

set_docid_order <order>

Set the direction in which documents are ordered by document id in the returned MSet.

This order only has an effect on documents which would otherwise have equal rank. For a weighted probabilistic match with no sort value, this means documents with equal weight. For a boolean match, with no sort value, this means all documents. And if a sort value is used, this means documents with equal sort value (and also equal weight if ordering on relevance after the sort).

order can be ENQ_ASCENDING (the default, docids sort in ascending order), ENQ_DESCENDING (docds sort in descending order), or ENQ_DONT_CARE (docids sort in whatever order is most efficient for the backend.)

Note: If you add documents in strict date order, then a boolean search - i.e. set_weighting_scheme(Search::Xapian::BoolWeight->new()) - with set_docid_order(ENQ_DESCENDING) is a very efficient way to perform "sort by date, newest first".

set_cutoff <percent_cutoff> [<weight_cutoff>]

set_sort_by_relevance

Set the sorting to be by relevance only. This is the default.

set_sort_by_value <sort_key> [<ascending>]

Set the sorting to be by value only.

sort_key - value number to reorder on. Sorting is with a string compare. If ascending is true (the default) higher is better; if ascending is false, lower is better.

ascending - If true, document values which sort higher by string compare are better. If false, the sort order is reversed. (default true)

set_sort_by_value_then_relevance <sort_key> [<ascending>]

Set the sorting to be by value, then by relevance for documents with the same value.

sort_key - value number to reorder on. Sorting is with a string compare. If ascending is true (the default) higher is better; if ascending is false, lower is better.

ascending - If true, document values which sort higher by string compare are better. If false, the sort order is reversed. (default true)

set_sort_by_relevance_then_value <sort_key> [<ascending>]

Set the sorting to be by relevance then value.

Note that with the default BM25 weighting scheme parameters, non-identical documents will rarely have the same weight, so this setting will give very similar results to set_sort_by_relevance(). It becomes more useful with particular BM25 parameter settings (e.g. BM25Weight(1,0,1,0,0)) or custom weighting schemes.

sort_key - value number to reorder on. Sorting is with a string compare. If ascending is true (the default) higher is better; if ascending is false, lower is better.

ascending - If true, document values which sort higher by string compare are better. If false, the sort order is reversed. (default true)

set_sort_by_key <sorter> [<ascending>]

Set the sorting to be by key only.

sorter - the functor to use to build the key.

ascending - If true, keys which sort higher by string compare are better. If false, the sort order is reversed. (default true)

set_sort_by_key_then_relevance <sorter> [<ascending>]

Set the sorting to be by key, then by relevance for documents with the same key.

sorter - the functor to use to build the key.

ascending - If true, keys which sort higher by string compare are better. If false, the sort order is reversed. (default true)

set_sort_by_relevance_then_key <sorter> [<ascending>]

Set the sorting to be by relevance then key.

sorter - the functor to use to build the key.

ascending - If true, keys which sort higher by string compare are better. If false, the sort order is reversed. (default true)

get_mset

Get match set.

get_eset <maxitems> <rset> [<decider>]

Get set of query expansion terms.

get_description

Return a description of this object.

add_matchspy <spy>

Add a matchspy.

This matchspy will be called with some of the documents which match the query, during the match process.

clear_matchspies

Remove all the matchspies.

SEE ALSO¶

Search::Xapian::Query, Search::Xapian::Database, Search::Xapian::MatchSpy