Struct CollectionMetaValue 

pub struct CollectionMetaValue {
    pub schema_version: u32,
    pub dimensions: u16,
    pub distance_metric: DistanceMetric,
    pub chunk_target: u16,
    pub fields: Vec<MetadataFieldSpec>,
}

CollectionMeta value storing collection schema and configuration.

This is a singleton record (one per collection) that defines the structure all vectors must conform to. It is read on startup and cached in memory.

Value Layout (little-endian)

┌────────────────────────────────────────────────────────────────┐
│  schema_version:    u32                                        │
│  dimensions:        u16                                        │
│  distance_metric:   u8   (0=L2, 2=dot_product)                  │
│  chunk_target:      u16  (centroids per chunk, default 4096)   │
│  metadata_fields:   Array<MetadataFieldSpec>                   │
│                                                                │
│  MetadataFieldSpec                                             │
│  ┌──────────────────────────────────────────────────────────┐  │
│  │  name:       Utf8                                        │  │
│  │  field_type: u8  (0=string, 1=int64, 2=float64, 3=bool)  │  │
│  │  indexed:    u8  (0=false, 1=true)                       │  │
│  └──────────────────────────────────────────────────────────┘  │
└────────────────────────────────────────────────────────────────┘

Fields

schema_version: u32

Monotonically increasing version for metadata schema changes.

Incremented when metadata fields are added or indexing is enabled. Does not change for vector insertions/deletions.

dimensions: u16

Fixed dimensionality for all vectors (immutable after creation).

Common values: 384 (MiniLM), 768 (BERT), 1536 (OpenAI ada-002).

distance_metric: DistanceMetric

Distance function for similarity computation (immutable after creation).

chunk_target: u16

Target number of centroids per CentroidChunk (immutable after creation).

Default is 4096, which yields ~25 MB per chunk at 1536 dimensions.

fields: Vec<MetadataFieldSpec>

Schema for fields attached to vectors.

Defines field names, types, and whether each field is indexed for filtering.

Implementations

impl CollectionMetaValue

pub fn new( dimensions: u16, distance_metric: DistanceMetric, chunk_target: u16, metadata_fields: Vec<MetadataFieldSpec>, ) -> Self

pub fn encode_to_bytes(&self) -> Bytes

pub fn decode_from_bytes(buf: &[u8]) -> Result<Self, EncodingError>

pub fn get_field(&self, name: &str) -> Option<&MetadataFieldSpec>

Find a metadata field spec by name.

pub fn indexed_fields(&self) -> impl Iterator<Item = &str>

Returns the names of all indexed fields.

Trait Implementations

impl Clone for CollectionMetaValue

fn clone(&self) -> CollectionMetaValue

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CollectionMetaValue

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

Formats the value using the given formatter.

impl PartialEq for CollectionMetaValue

fn eq(&self, other: &CollectionMetaValue) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for CollectionMetaValue

impl StructuralPartialEq for CollectionMetaValue