Struct tantivy::SegmentReader

pub struct SegmentReader { /* fields omitted */ }

Entry point to access all of the datastructures of the Segment

• term dictionary
• postings
• store
• fast field readers
• field norm reader

The segment reader has a very low memory footprint, as close to all of the memory data is mmapped.

Methods

impl SegmentReader

pub fn max_doc(&self) -> DocId

Returns the highest document id ever attributed in this segment + 1. Today, tantivy does not handle deletes, so it happens to also be the number of documents in the index.

pub fn num_docs(&self) -> DocId

Returns the number of documents. Deleted documents are not counted.

Today, tantivy does not handle deletes so max doc and num_docs are the same.

pub fn num_deleted_docs(&self) -> DocId

Return the number of documents that have been deleted in the segment.

pub fn get_fast_field_reader<TFastFieldReader: FastFieldReader>(
    &self,
    field: Field
) -> Result<TFastFieldReader>

Accessor to a segment's fast field reader given a field.

Returns the u64 fast value reader if the field is a u64 field indexed as "fast".

Return a FastFieldNotAvailableError if the field is not declared as a fast field in the schema.

Panics

May panic if the index is corrupted.

pub fn facet_reader(&self, field: Field) -> Result<FacetReader>

Accessor to the FacetReader associated to a given Field.

pub fn multi_value_reader(
    &self,
    field: Field
) -> Result<MultiValueIntFastFieldReader>

Accessor to the MultiValueIntFastFieldReader associated to a given Field.

pub fn get_fieldnorms_reader(&self, field: Field) -> Option<U64FastFieldReader>

Accessor to the segment's Field norms's reader.

Field norms are the length (in tokens) of the fields. It is used in the computation of the [TfIdf] (https://fulmicoton.gitbooks.io/tantivy-doc/content/tfidf.html).

They are simply stored as a fast field, serialized in the .fieldnorm file of the segment.

pub fn get_store_reader(&self) -> &StoreReader

Accessor to the segment's StoreReader.

pub fn open(segment: &Segment) -> Result<SegmentReader>

Open a new segment for reading.

pub fn inverted_index(&self, field: Field) -> Arc<InvertedIndexReader>

Returns a field reader associated to the field given in argument.

The field reader is in charge of iterating through the term dictionary associated to a specific field, and opening the posting list associated to any term.

pub fn doc(&self, doc_id: DocId) -> Result<Document>

Returns the document (or to be accurate, its stored field) bearing the given doc id. This method is slow and should seldom be called from within a collector.

pub fn segment_id(&self) -> SegmentId

Returns the segment id

pub fn delete_bitset(&self) -> &DeleteBitSet

Returns the bitset representing the documents that have been deleted.

pub fn is_deleted(&self, doc: DocId) -> bool

Returns true iff the doc is marked as deleted.

Trait Implementations

impl Clone for SegmentReader

fn clone(&self) -> SegmentReader

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SegmentReader

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.