Lucy::Index::DeletionsWriter(3) Abstract base class for marking documents as deleted.


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 );


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.


delete_by_term( [labeled params] )

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 "field" is associated with an Analyzer, "term" will be processed automatically (so don't pre-process it yourself).


Delete all documents in the index that match "query".
  • query - A Query.


Returns true if there are updates that need to be written.


Return the number of deletions for a given segment.
  • seg_name - The name of the segment.


Lucy::Index::DeletionsWriter isa Lucy::Index::DataWriter isa Lucy::Object::Obj.