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Query Parameters

Query parameters control search-time behavior for vector queries. Each index type has its own query parameter class.

Inheritance Hierarchy

QueryParams (abstract)
  ├── HnswQueryParams
  ├── IVFQueryParams
  └── FlatQueryParams

QueryParams (Base)

Shared by all query parameter types:

Method Returns Description
type IndexType Index type this applies to
radius Float Max distance threshold
radius= Set max distance threshold
linear? Boolean Force linear (brute-force) scan
linear= Set linear scan mode
using_refiner? Boolean Re-rank with exact distances
using_refiner= Set refiner mode

HnswQueryParams

qp = Zvec::HnswQueryParams.new(ef: 300, radius: 0.0, is_linear: false, is_using_refiner: false)
Parameter Type Default Description
ef Integer 300 Search width at query time
radius Float 0.0 Max distance (0 = unlimited)
is_linear Boolean false Bypass HNSW, use brute force
is_using_refiner Boolean false Re-rank candidates exactly

Instance methods:

Method Returns Description
ef Integer Search width
ef= Set search width

IVFQueryParams

qp = Zvec::IVFQueryParams.new(nprobe: 10, is_using_refiner: false, scale_factor: 10.0)
Parameter Type Default Description
nprobe Integer 10 Number of clusters to search
is_using_refiner Boolean false Re-rank candidates exactly
scale_factor Float 10.0 Internal scaling parameter

Instance methods:

Method Returns Description
nprobe Integer Clusters to search
nprobe= Set probe count
scale_factor Float Scale factor
scale_factor= Set scale factor

FlatQueryParams

qp = Zvec::FlatQueryParams.new(is_using_refiner: false, scale_factor: 10.0)
Parameter Type Default Description
is_using_refiner Boolean false Re-rank candidates
scale_factor Float 10.0 Internal scaling parameter

Instance methods:

Method Returns Description
scale_factor Float Scale factor
scale_factor= Set scale factor

Usage with query_vector

Pass query params as the query_params keyword argument:

qp = Zvec::HnswQueryParams.new(ef: 500)
results = col.query_vector("embedding", query_vec, top_k: 10, query_params: qp)