---
warning: DO NOT CHANGE THIS MANUALLY, THIS IS GENERATED BY https://github/duckdb/community-extensions repository, check README there
title: vindex
excerpt: |
  DuckDB Community Extensions
  Approximate nearest-neighbor vector indexes (HNSW / IVF / DiskANN / SPANN) with pluggable quantizers (Flat / RaBitQ / PQ / ScaNN)

extension:
  name: vindex
  description: Approximate nearest-neighbor vector indexes (HNSW / IVF / DiskANN / SPANN) with pluggable quantizers (Flat / RaBitQ / PQ / ScaNN)
  version: 0.1.0
  language: C++
  build: cmake
  license: MIT
  excluded_platforms: "wasm_mvp;wasm_eh;wasm_threads"
  maintainers:
    - Icemap

repo:
  github: Icemap/duckdb-vector-index
  ref: v0.1.0

docs:
  hello_world: |
    INSTALL vindex FROM community;
    LOAD vindex;

    -- Store 1536-dim embeddings and index them with HNSW + 3-bit RaBitQ.
    CREATE TABLE docs (id INTEGER, embedding FLOAT[1536]);
    -- ... insert rows ...
    CREATE INDEX docs_hnsw ON docs USING HNSW (embedding)
        WITH (metric = 'cosine', quantizer = 'rabitq', bits = 3);

    -- Approximate top-10 nearest neighbours (the planner rewrites this to an
    -- index scan; add `SET vindex_hnsw_ef_search = 200;` to trade recall vs
    -- latency at query time).
    SELECT id
    FROM docs
    ORDER BY array_cosine_distance(embedding, [0.1, 0.2, /* ... */]::FLOAT[1536])
    LIMIT 10;

  extended_description: |
    vindex ships four approximate-nearest-neighbour index types and four
    quantizers that can be mixed at `CREATE INDEX` time:

    Algorithms:
      * HNSW    — hierarchical navigable small world graph; the go-to in-memory
                  baseline.
      * IVF     — inverted-file / coarse clustering; small memory footprint,
                  `nprobe` lets you trade recall vs latency.
      * DiskANN — Vamana graph with the vector codes held separately from the
                  graph blocks, so the graph can exceed RAM while queries stay
                  fast. Requires a compressing quantizer (rabitq / pq / scann).
      * SPANN   — IVF with closure-replica writes; higher recall than IVF at
                  the same `nprobe`.

    Quantizers:
      * flat    — identity, exact distances, full fp32 storage.
      * rabitq  — b-bit RaBitQ (SIGMOD 2024). Supports L2SQ, IP, and cosine.
      * pq      — product quantization (L2SQ / IP). Rejects cosine.
      * scann   — anisotropic PQ (ICML 2020; L2SQ / IP). Rejects cosine.

    Supported DuckDB distance functions: `array_distance`, `array_cosine_distance`,
    `array_negative_inner_product`. The planner rewrites `ORDER BY <distance>
    LIMIT k` into a `VINDEX_INDEX_SCAN` operator whenever a matching index exists.

    Session pragmas let you tune search-time recall without rebuilding the
    index (e.g. `SET vindex_hnsw_ef_search = 200`, `SET vindex_ivf_nprobe = 32`,
    `SET vindex_diskann_l_search = 100`).

    See https://github.com/Icemap/duckdb-vector-index for the full acceptance
    matrix, supported `WITH` options per algorithm, and persistence semantics.

extension_star_count: 8
extension_star_count_pretty: 8
extension_download_count: 1052
extension_download_count_pretty: 1.1k
image: '/images/community_extensions/social_preview/preview_community_extension_vindex.png'
layout: community_extension_doc
---

### Installing and Loading
```sql
INSTALL {{ page.extension.name }} FROM community;
LOAD {{ page.extension.name }};
```

{% if page.docs.hello_world %}
### Example
```sql
{{ page.docs.hello_world }}```
{% endif %}

{% if page.docs.extended_description %}
### About {{ page.extension.name }}
{{ page.docs.extended_description }}
{% endif %}

### Added Functions

<div class="extension_functions_table"></div>

|          function_name           | function_type | description | comment | examples |
|----------------------------------|---------------|-------------|---------|----------|
| hnsw_compact_index               | pragma        | NULL        | NULL    |          |
| pragma_hnsw_index_info           | table         | NULL        | NULL    |          |
| pragma_vindex_diskann_index_info | table         | NULL        | NULL    |          |
| pragma_vindex_hnsw_index_info    | table         | NULL        | NULL    |          |
| pragma_vindex_ivf_index_info     | table         | NULL        | NULL    |          |
| pragma_vindex_spann_index_info   | table         | NULL        | NULL    |          |
| vindex_compact_index             | pragma        | NULL        | NULL    |          |
| vindex_index_scan                | table         | NULL        | NULL    |          |
| vindex_join                      | table_macro   | NULL        | NULL    |          |
| vindex_match                     | table_macro   | NULL        | NULL    |          |
| vss_join                         | table_macro   | NULL        | NULL    |          |
| vss_match                        | table_macro   | NULL        | NULL    |          |

### Overloaded Functions

<div class="extension_functions_table"></div>

This extension does not add any function overloads.

### Added Types

<div class="extension_types_table"></div>

This extension does not add any types.

### Added Settings

<div class="extension_settings_table"></div>

|                  name                  |                                                                            description                                                                            | input_type | scope  | aliases |
|----------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------|--------|---------|
| hnsw_ef_search                         | deprecated alias of vindex_ef_search                                                                                                                              | BIGINT     | GLOBAL | []      |
| hnsw_enable_experimental_persistence   | deprecated alias of vindex_enable_experimental_persistence                                                                                                        | BOOLEAN    | GLOBAL | []      |
| vindex_diskann_l_search                | override the DiskANN beam width (L_search) when scanning                                                                                                          | BIGINT     | GLOBAL | []      |
| vindex_ef_search                       | override the ef_search parameter when scanning HNSW indexes                                                                                                       | BIGINT     | GLOBAL | []      |
| vindex_enable_experimental_persistence | experimental: enable creating vector indexes in persistent databases                                                                                              | BOOLEAN    | GLOBAL | []      |
| vindex_nprobe                          | override the nprobe parameter when scanning IVF indexes                                                                                                           | BIGINT     | GLOBAL | []      |
| vindex_rerank_multiple                 | override the rerank over-fetch factor when scanning vector indexes (index returns k × rerank_multiple candidates; upstream TopN/min_by reranks by exact distance) | BIGINT     | GLOBAL | []      |