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( [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_by_query(query)

Delete all documents in the index that match query.

• query - A Query.

updated()

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

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 Lucy::Object::Obj.