Struct Collection 

pub struct Collection { /* private fields */ }

A collection of vectors with associated metadata.

Implementations

impl Collection

pub fn create( path: PathBuf, dimension: usize, metric: DistanceMetric, ) -> Result<Self>

Creates a new collection at the specified path.

Errors

Returns an error if the directory cannot be created or the config cannot be saved.

pub fn create_with_options( path: PathBuf, dimension: usize, metric: DistanceMetric, storage_mode: StorageMode, ) -> Result<Self>

Creates a new collection with custom storage options.

Arguments

• path - Path to the collection directory
• dimension - Vector dimension
• metric - Distance metric
• storage_mode - Vector storage mode (Full, SQ8, Binary)

Errors

Returns an error if the directory cannot be created or the config cannot be saved.

pub fn open(path: PathBuf) -> Result<Self>

Opens an existing collection from the specified path.

Errors

Returns an error if the config file cannot be read or parsed.

pub fn config(&self) -> CollectionConfig

Returns the collection configuration.

pub fn upsert(&self, points: impl IntoIterator<Item = Point>) -> Result<()>

Inserts or updates points in the collection.

Accepts any iterator of points (Vec, slice, array, etc.)

Errors

Returns an error if any point has a mismatched dimension.

pub fn upsert_bulk(&self, points: &[Point]) -> Result<usize>

Bulk insert optimized for high-throughput import.

Performance

This method is optimized for bulk loading:

• Uses sequential HNSW insertion (reliable, no rayon conflicts)
• Single flush at the end (not per-point)
• No HNSW index save (deferred for performance)
• ~20-30% faster than previous parallel approach on large batches (5000+)
• Benchmark: 1.5-2.1 Kvec/s on 768D vectors

Errors

Returns an error if any point has a mismatched dimension.

pub fn get(&self, ids: &[u64]) -> Vec<Option<Point>>

Retrieves points by their IDs.

pub fn delete(&self, ids: &[u64]) -> Result<()>

Deletes points by their IDs.

Errors

Returns an error if storage operations fail.

pub fn search(&self, query: &[f32], k: usize) -> Result<Vec<SearchResult>>

Searches for the k nearest neighbors of the query vector.

Uses HNSW index for fast approximate nearest neighbor search.

Errors

Returns an error if the query vector dimension doesn’t match the collection.

pub fn search_with_ef( &self, query: &[f32], k: usize, ef_search: usize, ) -> Result<Vec<SearchResult>>

Performs vector similarity search with custom ef_search parameter.

Higher ef_search = better recall, slower search. Default ef_search is 128 (Balanced mode).

Errors

Returns an error if the query vector dimension doesn’t match the collection.

pub fn search_ids(&self, query: &[f32], k: usize) -> Result<Vec<(u64, f32)>>

Performs fast vector similarity search returning only IDs and scores.

Perf: This is ~3-5x faster than search() because it skips vector/payload retrieval. Use this when you only need IDs and scores, not full point data.

Arguments

• query - Query vector
• k - Maximum number of results to return

Returns

Vector of (id, score) tuples sorted by similarity.

Errors

Returns an error if the query vector dimension doesn’t match the collection.

pub fn search_batch_parallel( &self, queries: &[&[f32]], k: usize, ) -> Result<Vec<Vec<SearchResult>>>

Performs batch vector similarity search in parallel using rayon.

Perf: This is significantly faster than calling search in a loop because it parallelizes across CPU cores and amortizes lock overhead.

Arguments

• queries - Slice of query vectors
• k - Maximum number of results per query

Returns

Vector of search results for each query, with full point data.

Errors

Returns an error if any query vector dimension doesn’t match the collection.

pub fn len(&self) -> usize

Returns the number of points in the collection. Perf: Uses cached point_count from config instead of acquiring storage lock

pub fn is_empty(&self) -> bool

Returns true if the collection is empty. Perf: Uses cached point_count from config instead of acquiring storage lock

pub fn flush(&self) -> Result<()>

Saves the collection configuration and index to disk.

Errors

Returns an error if storage operations fail.

pub fn text_search(&self, query: &str, k: usize) -> Vec<SearchResult>

Performs full-text search using BM25.

Arguments

• query - Text query to search for
• k - Maximum number of results to return

Returns

Vector of search results sorted by BM25 score (descending).

pub fn hybrid_search( &self, vector_query: &[f32], text_query: &str, k: usize, vector_weight: Option<f32>, ) -> Result<Vec<SearchResult>>

Performs hybrid search combining vector similarity and full-text search.

Uses Reciprocal Rank Fusion (RRF) to combine results from both searches.

Arguments

• vector_query - Query vector for similarity search
• text_query - Text query for BM25 search
• k - Maximum number of results to return
• vector_weight - Weight for vector results (0.0-1.0, default 0.5)

Errors

Returns an error if the query vector dimension doesn’t match.

Trait Implementations

impl Clone for Collection

fn clone(&self) -> Collection

Returns a duplicate of the value.

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

Performs copy-assignment from source.