---
warning: DO NOT CHANGE THIS MANUALLY, THIS IS GENERATED BY https://github.com/duckdb/community-extensions repository, check README there
title: mqtt
excerpt: |
  DuckDB Community Extensions
  MQTT message ingestion for DuckDB — mqtt_scan() subscribes to any broker topic (wildcards supported) and returns messages as SQL rows, via pure-Rust rumqttc, no native broker library

extension:
  name: mqtt
  description: MQTT message ingestion for DuckDB — mqtt_scan() subscribes to any broker topic (wildcards supported) and returns messages as SQL rows, via pure-Rust rumqttc, no native broker library
  version: 0.1.0
  language: Rust
  build: cargo
  license: MIT
  excluded_platforms: "wasm_mvp;wasm_eh;wasm_threads;windows_amd64_rtools;windows_amd64_mingw;linux_amd64_musl"
  requires_toolchains: "rust;python3"
  maintainers:
    - alitrack

repo:
  github: alitrack/duckdb_mqtt
  ref: 244c376534cdc1d10e6eb56aba705613723f8c27
  ref_next: 244c376534cdc1d10e6eb56aba705613723f8c27

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

    -- Collect up to 100 messages on all topics within 10 seconds
    SELECT * FROM mqtt_scan('localhost', '#', 100, 10);

    -- Only sensor telemetry, as a table
    SELECT received_at, topic, payload
    FROM mqtt_scan('test.mosquitto.org', 'factory/+/temperature', 50, 30);

  extended_description: |
    ## mqtt — MQTT Message Ingestion for DuckDB

    A native Rust DuckDB loadable extension that subscribes to any
    [MQTT](https://mqtt.org) broker and returns the received messages as SQL
    rows — powered by pure-Rust [rumqttc](https://github.com/bytebeamio/rumqttc)
    (MQTT 3.1.1/5), written against DuckDB's C Extension API (ABI v1.2.0)
    through [quack-rs](https://github.com/tomtom215/quack-rs). No native broker
    library, no Python, no background services.

    Each `mqtt_scan` call is a bounded one-shot subscription: connect →
    subscribe → collect → disconnect. It fits DuckDB's table-function pull
    model — no threads outlive the query.

    ### Functions

    | Function | Description |
    |---|---|
    | `mqtt_scan(url, topic, max_messages, timeout_secs)` | Subscribe to `topic` on `url`, collect up to `max_messages` within `timeout_secs` → table |
    | `mqtt_version()` | Build/engine info string |

    `mqtt_scan` columns: `received_at TIMESTAMP, topic VARCHAR, qos TINYINT,
    retain BOOLEAN, payload VARCHAR (lossy UTF-8), payload_bytes BLOB (lossless)`.

    Arguments are bind-time constants (literals). `url` accepts `host`,
    `host:port`, `mqtt://…`, `mqtts://…` (default ports 1883/8883). `topic`
    supports MQTT wildcards (`+` single level, `#` multi-level). The scan
    stops at `max_messages` or `timeout_secs`, whichever hits first.
    Retained messages matching the filter are delivered on subscribe, which
    makes deterministic one-shot tests easy. Connection failures yield zero
    rows, never an abort.

    ```sql
    -- Per-topic message rates straight from the broker
    SELECT topic, count(*) AS n, avg(length(payload)) AS avg_len
    FROM mqtt_scan('localhost', '#', 1000, 60)
    GROUP BY topic ORDER BY n DESC;

    -- Raw bytes for binary payloads (protobufs, CBOR, …)
    SELECT topic, payload_bytes FROM mqtt_scan('localhost', 'telemetry/#', 10, 5);
    ```

    Long-running streaming ingest is out of scope for v1; the recommended
    pattern is periodic incremental scans keyed on `received_at`.

    Windows and musl builds are excluded pending CI coverage, matching the
    other quack-rs based community extensions.

    →  [GitHub](https://github.com/alitrack/duckdb_mqtt)

extension_star_count: 0
extension_star_count_pretty: 0
extension_download_count: 62
extension_download_count_pretty: 62
image: '/images/community_extensions/social_preview/preview_community_extension_mqtt.png'
layout: community_extension_doc
---
### Compatibility Matrix

This table covers all DuckDB releases that have not reached [end-of-life](https://duckdb.org/release_calendar), including LTS releases, and shows the 2 most recent patch releases of each. Older patch releases are not listed, but the extension may be available for them as well.

<div class="extension_compatibility_table"></div>

| Platform | 1.4.4 | 1.4.5 | 1.5.5 | 1.5.6 | 2.0.0 |
| :--- | :---: | :---: | :---: | :---: | :---: |
| Linux AMD64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| Linux ARM64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| macOS AMD64 | ❌ | ❌ | ❌ | ❌ | ❌ |
| macOS ARM64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| Windows AMD64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| Windows ARM64 | ❌ | ❌ | ❌ | ❌ | ❌ |
| WebAssembly | ❌ | ❌ | ❌ | ❌ | ❌ |

### 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 |
|---------------|---------------|-------------|---------|----------|
| mqtt_scan     | table         | NULL        | NULL    |          |
| mqtt_version  | scalar        | 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 | typed_value |
|----------------|---------------------------------------------------------|------------|--------|---------|-------------|
| temp_directory | Set the directory to which temporary files are written. | VARCHAR    | GLOBAL | []      | post.db.tmp |