NAME
Lucy::Index::DeletionsWriter - Abstract base class for marking documents as deleted.
SYNOPSIS
my $polyreader = $del_writer->get_polyreader;
my $seg_readers = $polyreader->seg_readers;
for my $seg_reader (@$seg_readers) {
my $count = $del_writer->seg_del_count( $seg_reader->get_seg_name );
...
}DESCRIPTION
Subclasses of DeletionsWriter provide a low-level mechanism for declaring a document deleted from an index.
Because files in an index are never modified, and because it is not practical to delete entire segments, a DeletionsWriter does not actually remove documents from the index. Instead, it communicates to a search-time companion DeletionsReader which documents are deleted in such a way that it can create a Matcher iterator.
Documents are truly deleted only when the segments which contain them are merged into new ones.
ABSTRACT METHODS
delete_by_term
$deletions_writer->delete_by_term(
field => $field, # required
term => $term, # required
);Delete all documents in the index that index the supplied term.
field - The name of an indexed field. (If it is not spec’d as
indexed, an error will occur.)term - The term which identifies docs to be marked as deleted. If
fieldis associated with an Analyzer,termwill be processed automatically (so don’t pre-process it yourself).
delete_by_query
$deletions_writer->delete_by_query($query);Delete all documents in the index that match query.
query - A Query.
updated
my $bool = $deletions_writer->updated();Returns true if there are updates that need to be written.
seg_del_count
my $int = $deletions_writer->seg_del_count($seg_name);Return the number of deletions for a given segment.
seg_name - The name of the segment.
INHERITANCE
Lucy::Index::DeletionsWriter isa Lucy::Index::DataWriter isa Clownfish::Obj.