mirror of
https://github.com/supabase/supabase.git
synced 2026-10-11 20:35:07 +03:00
42 lines
2.3 KiB
Plaintext
42 lines
2.3 KiB
Plaintext
---
|
|
id: 'ai-vector-indexes'
|
|
title: 'Vector indexes'
|
|
description: 'Understanding vector indexes'
|
|
sidebar_label: 'Vector indexes'
|
|
---
|
|
|
|
Once your vector table starts to grow, you will likely want to add an index to speed up queries. Without indexes, you'll be performing a sequential scan which can be a resource-intensive operation when you have many records.
|
|
|
|
## Choosing an index
|
|
|
|
Today `pgvector` supports two types of indexes:
|
|
|
|
- [HNSW](/docs/guides/ai/vector-indexes/hnsw-indexes)
|
|
- [IVFFlat](/docs/guides/ai/vector-indexes/ivf-indexes)
|
|
|
|
In general we recommend using [HNSW](/docs/guides/ai/vector-indexes/hnsw-indexes) because of its [performance](/blog/increase-performance-pgvector-hnsw#hnsw-performance-1536-dimensions) and [robustness against changing data](/docs/guides/ai/vector-indexes/hnsw-indexes#when-should-you-create-hnsw-indexes).
|
|
|
|
## Distance operators
|
|
|
|
Indexes can be used to improve performance of nearest neighbor search using various distance measures. `pgvector` includes 3 distance operators:
|
|
|
|
| Operator | Description | [**Operator class**](https://www.postgresql.org/docs/current/sql-createopclass.html) |
|
|
| -------- | ---------------------- | ------------------------------------------------------------------------------------ |
|
|
| `<->` | Euclidean distance | `vector_l2_ops` |
|
|
| `<#>` | negative inner product | `vector_ip_ops` |
|
|
| `<=>` | cosine distance | `vector_cosine_ops` |
|
|
|
|
For pgvector versions 0.7.0 and above, it's possible to create indexes on vectors with the following maximum dimensions:
|
|
|
|
- vector: up to 2,000 dimensions
|
|
- halfvec: up to 4,000 dimensions
|
|
- bit: up to 64,000 dimensions
|
|
|
|
You can check your current pgvector version by running: `SELECT * FROM pg_extension WHERE extname = 'vector';` or by navigating to the [Extensions](/dashboard/project/_/database/extensions) tab in your Supabase project dashboard.
|
|
|
|
If you are on an earlier version of pgvector, you should [upgrade your project here](/dashboard/project/_/settings/infrastructure).
|
|
|
|
## Resources
|
|
|
|
Read more about indexing on `pgvector`'s [GitHub page](https://github.com/pgvector/pgvector#indexing).
|