---
title: "Update collection"
method: PATCH
path: "/collections/{collection_name}"
tags: ["Collections"]
---

# Update collection

`PATCH /collections/{collection_name}`

Update parameters of an existing collection, such as optimizer configuration and HNSW search settings. Vector dimension and distance metric cannot be changed after creation.

## Path parameters

- `collection_name` string, required

## Query parameters

- `timeout` integer

## Request body

- object
  - `optimizers_config` object — Optimizer settings for indexing thresholds and vacuum behavior.
    - `indexing_threshold` integer — The minimum number of vectors before indexing is triggered.
  - `hnsw_config` object — HNSW index parameters that can be updated after creation.
    - `ef_search` integer — The size of the dynamic candidate list during search.

## Response `200`

Collection updated

- object
  - `usage` object
    - `hardware` object, nullable — Hardware resource counters for the operation, including CPU, payload I/O, payload index I/O, and vector I/O metrics.
  - `time` number, double — Time spent to process this request, in seconds.
  - `status` string — Operation status.
  - `result` boolean — Whether the operation completed successfully.

---

[API](https://skmtc.net/actiancorp/apis/actian-vectorai-db-collections-api.md) · [All operations](https://skmtc.net/actiancorp/apis/actian-vectorai-db-collections-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/actiancorp/actian-vectorai-db-collections-api/versions/af01467a9a12/schema)