---
title: "database_observability.mysql | Grafana Alloy documentation"
description: "Learn about database_observability.mysql"
---

> For a curated documentation index, see [llms.txt](/llms.txt). For the complete documentation index, see [llms-full.txt](/llms-full.txt).

# `database_observability.mysql`

`database_observability.mysql` connects to a MySQL database and collects observability data from the `performance_schema` and `information_schema`. The component collects query details, schema information, explain plans, query samples, and lock information. It forwards this data as log entries to Loki receivers and exports targets for Prometheus scraping.

## Usage

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```alloy
database_observability.mysql "<LABEL>" {
  data_source_name = <DATA_SOURCE_NAME>
  forward_to       = [<LOKI_RECEIVERS>]
}
```

## Arguments

You can use the following arguments with `database_observability.mysql`:

Expand table

| Name                                       | Type                 | Description                                                                                                                                                                  | Default                                                                                              | Required |
|--------------------------------------------|----------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------|----------|
| `data_source_name`                         | `secret`             | [Data Source Name](https://github.com/go-sql-driver/mysql#dsn-data-source-name) for the MySQL server to connect to. Required when no `database_instance` blocks are defined. |                                                                                                      | no       |
| `forward_to`                               | `list(LogsReceiver)` | Where to forward log entries after processing.                                                                                                                               |                                                                                                      | yes      |
| `targets`                                  | `list(map(string))`  | List of external targets to scrape.                                                                                                                                          |                                                                                                      | no       |
| `disable_collectors`                       | `list(string)`       | A list of collectors to disable from the default set.                                                                                                                        |                                                                                                      | no       |
| `enable_collectors`                        | `list(string)`       | A list of collectors to enable on top of the default set.                                                                                                                    |                                                                                                      | no       |
| `exclude_schemas`                          | `list(string)`       | A list of schemas to exclude from monitoring.                                                                                                                                | `["alloydbadmin", "alloydbmetadata", "azure_maintenance", "azure_sys", "cloudsqladmin", "rdsadmin"]` | no       |
| `allow_update_performance_schema_settings` | `boolean`            | Whether to allow updates to `performance_schema` settings in any collector. Enable this in conjunction with other collector-specific settings where required.                | `false`                                                                                              | no       |

The following collectors are configurable:

Expand table

| Name              | Description                                                  | Enabled by default |
|-------------------|--------------------------------------------------------------|--------------------|
| `query_details`   | Collect queries information.                                 | yes                |
| `schema_details`  | Collect schemas and tables from `information_schema`.        | yes                |
| `query_samples`   | Collect query samples.                                       | yes                |
| `setup_consumers` | Collect enabled `performance_schema.setup_consumers`.        | yes                |
| `setup_actors`    | Check and update `performance_schema.setup_actors` settings. | yes                |
| `locks`           | Collect queries that are waiting/blocking other queries.     | no                 |
| `explain_plans`   | Collect explain plans information.                           | yes                |
| `table_stats`     | Collect table-level index usage statistics.                  | no                 |
| `index_stats`     | Collect per-index usage statistics.                          | no                 |

## Blocks

You can use the following blocks with `database_observability.mysql`:

No valid configuration blocks found.

### `cloud_provider`

The `cloud_provider` block has no attributes. It contains zero or one of the [`aws`](#aws), [`azure`](#azure), or [`gcp`](#gcp) blocks. You use the `cloud_provider` block to provide information related to the cloud provider that hosts the database under observation. This information is appended as labels to the collected metrics. The labels make it easier for you to filter and group your metrics.

### `aws`

The `aws` block supplies the [ARN](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference-arns.html) identifier for the database being monitored.

Expand table

| Name  | Type     | Description                                             | Default | Required |
|-------|----------|---------------------------------------------------------|---------|----------|
| `arn` | `string` | The ARN associated with the database under observation. |         | yes      |

### `azure`

The `azure` block supplies the identifying information for the database being monitored.

Expand table

| Name              | Type     | Description                                                                                          | Default | Required |
|-------------------|----------|------------------------------------------------------------------------------------------------------|---------|----------|
| `subscription_id` | `string` | The Subscription ID for your Azure account.                                                          |         | yes      |
| `resource_group`  | `string` | The Resource Group that holds the database resource.                                                 |         | yes      |
| `server_name`     | `string` | The database server name, for example `orders-db` for the host `orders-db.mysql.database.azure.com`. |         | no       |

### `gcp`

The `gcp` block supplies the identifying information for the GCP Cloud SQL database being monitored.

Expand table

| Name              | Type     | Description                                                                                                                 | Default | Required |
|-------------------|----------|-----------------------------------------------------------------------------------------------------------------------------|---------|----------|
| `connection_name` | `string` | The Cloud SQL instance connection name in the format `project:region:instance`, for example `my-project:us-central1:my-db`. |         | yes      |

### `database_instance`

The `database_instance` block defines one database server to monitor. Repeat the block to monitor several databases with a single component. The block label must be unique across `database_instance` blocks and identifies the database in the component’s metrics endpoint path. Each `database_instance` block must also point to a distinct server: two blocks that resolve to the same host, port, and database name are rejected.

Expand table

| Name               | Type     | Description                                                                                                         | Default | Required |
|--------------------|----------|---------------------------------------------------------------------------------------------------------------------|---------|----------|
| `data_source_name` | `secret` | [Data Source Name](https://github.com/go-sql-driver/mysql#dsn-data-source-name) for the MySQL server to connect to. |         | yes      |

Each `database_instance` block can also contain a \[`cloud_provider`]\[cloud\_provider] block that applies to that database only, and \[`rule`]\[rule] blocks that relabel the metrics and logs of that database only.

The component always embeds a `mysqld_exporter` for each `database_instance` block and serves its metrics on the block’s metrics path. Use the \[`prometheus_exporter`]\[prometheus\_exporter] block to configure it. External exporter targets are only supported in the top-level single-DSN form.

When you define `database_instance` blocks, don’t set the top-level `data_source_name`, `targets`, and `cloud_provider` arguments. They’re mutually exclusive with `database_instance` blocks. All other arguments and blocks, such as collector settings and `prometheus_exporter`, apply to every configured database.

The metrics for each database are served on a separate `/db/<LABEL>/metrics` path under the component’s HTTP endpoint, and the exported targets point to the corresponding path. When you don’t define `database_instance` blocks, the component serves metrics on its historical `/metrics` path. The metrics endpoints are served exactly at those paths: requests to any other path under the component’s HTTP endpoint return HTTP 404.

For example:

Alloy ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```alloy
database_observability.mysql "pool" {
  forward_to = [loki.write.logs_service.receiver]

  database_instance "orders" {
    data_source_name = sys.env("ORDERS_DSN")

    cloud_provider {
      aws {
        arn = "orders-rds-db-arn"
      }
    }

    rule {
      target_label = "environment"
      replacement  = "production"
    }
  }

  database_instance "billing" {
    data_source_name = sys.env("BILLING_DSN")

    rule {
      target_label = "environment"
      replacement  = "staging"
    }
  }
}
```

In this example, the metrics and logs of the `orders` database carry `environment="production"`, and those of the `billing` database carry `environment="staging"`.

### `rule`

The `rule` block relabels the metrics and the logs of the `database_instance` block that contains it. Use it to tell the data of each monitored database apart, for example by environment, team, or tier.

The `rule` block defines a relabeling rule applied to the metrics and the logs of a single monitored database. If you define more than one `rule` block, the rules are applied in top-down order, after the labels the component sets itself, so a rule can read those labels with `source_labels`.

It takes the same arguments as the [`rule` block](/docs/alloy/next/reference/components/prometheus/prometheus.relabel/#rule) used elsewhere in Alloy, in a restricted form: because one rule set applies to two signal paths, it supports the labelling actions only, and it can’t overwrite most of the labels the component sets. Alloy refuses to load a configuration containing a rule that breaks either restriction, so such a rule is never silently ignored.

Two further constraints are specific to a `database_instance` block:

- **`target_label` must be a literal label name**: Alloy checks it against the reserved labels when it loads the configuration, so it can’t contain a capture group reference.
- **`hashmod` requires `source_labels`, and can’t target `instance`** : hashing the empty value gives every database the same result, and hashing into `instance` buckets several databases onto one value even when the source is present.

> Caution
> 
> A relabeling rule that computes an empty value *removes* its target label instead of setting it, and the default `replacement` of `"$1"` computes an empty value when a rule has no `source_labels`. So `rule { target_label = "environment" }` removes `environment` rather than setting it, and Alloy rejects it. Always set `replacement` alongside a `target_label`.
> 
> Alloy can only reject such a rule where the outcome is certain. A rule that reads `source_labels` depends on the labels present at runtime, so a missing or misspelled source label still removes the target label, except for the reserved labels and `instance`, which keep their previous value. Only removal is prevented: a rule that computes a *non-empty* value still overwrites those labels, which is why `hashmod` can’t target `instance` at all.

You can use the `hashmod`, `labeldrop`, `lowercase`, `replace`, and `uppercase` actions. The rest aren’t supported:

- `drop`, `dropequal`, `keep`, and `keepequal` filter rather than label, and filtering means two different things on the two signal paths. Dropping a metrics target stops the database exporting metrics entirely, whereas dropping a log entry discards one line. To filter one database’s logs, use a [`loki.relabel`](/docs/alloy/next/reference/components/loki/loki.relabel/) component on the receiver named in `forward_to`, with a `drop` rule that matches that database’s `instance` or `server_id`. Every database the component monitors forwards to the same receivers, so the rule has to identify the one it applies to. To filter one database’s metrics, use a [`discovery.relabel`](/docs/alloy/next/reference/components/discovery/discovery.relabel/) component on the component’s exported targets.
- `labelmap` builds label names from `replacement` at runtime, so Alloy can’t check them against the reserved labels when it loads the configuration.
- `labelkeep` removes every label its `regex` doesn’t match, so a rule that preserves the reserved labels would have to match all of them. Use `labeldrop` to remove specific labels instead.

Because the rules run after the component’s own labels, and those are protected, a `labeldrop` rule can only remove a label that an earlier rule in the same block created.

#### Reserved labels

A rule can’t write to the following labels, and a `labeldrop` regular expression can’t match them:

- **Both metrics and logs**: `job` and `server_id`.
- **Logs only**: `engine` and `op`.
- **Metrics only**: `provider_name`, `provider_region`, `provider_account`, `__address__`, `__scheme__`, and `__metrics_path__`.

This applies to `rule` blocks only. A downstream `discovery.relabel` or `loki.relabel` component can still overwrite any of them, but it applies to every database the component monitors rather than one.

The `instance` label is a special case: a rule can rewrite its value, which is a common reason to use a `rule` block, because a friendly name such as `orders_db` then applies to that database’s metrics and logs together. A rule can’t remove it, because metrics and logs are correlated on it, and because an empty `instance` on a metrics target makes Prometheus fill it in from `__address__`, which every database in one component shares, collapsing them all onto one series.

For the same reason, two `database_instance` blocks can’t rewrite `instance` to the same value. Alloy rejects that when both values are fixed in the configuration, but it can’t when the value comes from a label the databases share: `source_labels = ["job"]` gives every database the same `instance`, since they all carry the same `job`. Derive `instance` from something that differs per database, or set a literal value in each block.

#### Labels set on only one signal path

Some of the labels above exist on one signal path and not the other, and a rule that reads one with `source_labels` behaves differently on each path: where the label is absent the rule computes an empty value, which *removes* its `target_label` rather than setting it to an empty string.

A rule reading `provider_region`, which a database with a [`cloud_provider`](#cloud_provider) block carries on its metrics targets but not on its log entries, sets `region` on that database’s metrics and removes `region` from its logs. Reading a logs-only label such as `op` does the same in reverse. Only `job`, `server_id`, and `instance` are set on both paths, so prefer those as `source_labels`, or a label an earlier rule in the same block created.

### `clustering`

Expand table

| Name      | Type   | Description                                              | Default | Required |
|-----------|--------|----------------------------------------------------------|---------|----------|
| `enabled` | `bool` | Enables distributing databases with other cluster nodes. | `false` | yes      |

When Alloy is [using clustering](../../../../get-started/clustering/), and `enabled` is set to true, then this `database_observability.mysql` component instance opts-in to distributing its configured databases between all cluster nodes.

Clustering assumes that all cluster nodes are running with the same configuration file. All component instances opting in to clustering use the instance key of each configured database, `<network>(<host>:<port>)/<dbname>`, and a consistent hashing algorithm to determine ownership of each database between the cluster peers. Each peer then only collects from the subset of databases it’s responsible for, and only exports the targets of those databases, so `prometheus.scrape` components on the same node scrape exactly the databases the node owns. When a node joins or leaves the cluster, every peer recalculates ownership: expect a short gap or a brief duplicate collection for a database while its ownership moves. This includes the collectors that update `performance_schema` settings, such as `setup_actors` and `setup_consumers`, which can briefly run from two nodes during the move: their updates are idempotent. While the cluster isn’t yet ready to admit traffic, for example while it’s still forming and waiting for the minimum cluster size, the component doesn’t collect from any database.

Clustering is also useful with a single database: when several cluster nodes run an identical configuration, exactly one node collects from the database at a time, which gives you a highly available setup without duplicate collection.

If Alloy is *not* running in clustered mode, then the block is a no-op and `database_observability.mysql` collects from every configured database.

### `setup_consumers`

Expand table

| Name               | Type       | Description                                                                                   | Default | Required |
|--------------------|------------|-----------------------------------------------------------------------------------------------|---------|----------|
| `collect_interval` | `duration` | How frequently to collect `performance_schema.setup_consumers` information from the database. | `"1h"`  | no       |

### `query_details`

Expand table

| Name               | Type       | Description                                          | Default | Required |
|--------------------|------------|------------------------------------------------------|---------|----------|
| `collect_interval` | `duration` | How frequently to collect information from database. | `"1m"`  | no       |
| `statements_limit` | `integer`  | Max number of recent queries to collect details for. | `250`   | no       |

### `schema_details`

Expand table

| Name               | Type       | Description                                                 | Default | Required |
|--------------------|------------|-------------------------------------------------------------|---------|----------|
| `collect_interval` | `duration` | How frequently to collect information from database.        | `"1m"`  | no       |
| `cache_enabled`    | `boolean`  | Deprecated. Whether to enable caching of table definitions. | `true`  | no       |
| `cache_size`       | `integer`  | Deprecated. Cache size.                                     | `256`   | no       |
| `cache_ttl`        | `duration` | Deprecated. Cache TTL.                                      | `"10m"` | no       |

The `cache_enabled`, `cache_size`, and `cache_ttl` settings are deprecated: they are accepted for backward compatibility, but ignored.

### `explain_plans`

Expand table

| Name                | Type       | Description                                                                     | Default | Required |
|---------------------|------------|---------------------------------------------------------------------------------|---------|----------|
| `collect_interval`  | `duration` | How frequently to collect information from database.                            | `"1m"`  | no       |
| `initial_lookback`  | `duration` | How far back to look for explain plan queries on the first collection interval. | `"24h"` | no       |
| `per_collect_ratio` | `float`    | Ratio of explain plan queries to collect per collect interval.                  | `1.0`   | no       |

### `locks`

Expand table

| Name               | Type       | Description                                                                            | Default | Required |
|--------------------|------------|----------------------------------------------------------------------------------------|---------|----------|
| `collect_interval` | `duration` | How frequently to collect information from database.                                   | `"30s"` | no       |
| `threshold`        | `duration` | Threshold for locks to be considered slow. Locks that exceed this duration are logged. | `"1s"`  | no       |

### `query_samples`

Expand table

| Name                                | Type       | Description                                                                                                                                   | Default | Required |
|-------------------------------------|------------|-----------------------------------------------------------------------------------------------------------------------------------------------|---------|----------|
| `collect_interval`                  | `duration` | How frequently to collect information from database.                                                                                          | `"10s"` | no       |
| `disable_query_redaction`           | `bool`     | Collect unredacted SQL query text (including query parameters) and query error messages.                                                      | `false` | no       |
| `auto_enable_setup_consumers`       | `boolean`  | Enables specific `performance_schema.setup_consumers` options. You must also enable `allow_update_performance_schema_settings`.               | `false` | no       |
| `setup_consumers_check_interval`    | `duration` | How frequently to check if `setup_consumers` are correctly enabled.                                                                           | `"1h"`  | no       |
| `sample_min_duration`               | `duration` | Minimum duration for query samples to be collected. Set to “0s” to disable filtering and collect all samples regardless of their duration.    | `"0s"`  | no       |
| `wait_event_min_duration`           | `duration` | Minimum duration for a wait event to be collected. Set to “0s” to disable filtering and collect all wait events regardless of their duration. | `"1us"` | no       |
| `enable_pre_classified_wait_events` | `boolean`  | When `true`, emits telemetry data with pre-classified wait event information.                                                                 | `false` | no       |

### `setup_actors`

Expand table

| Name                       | Type       | Description                                                                                                                     | Default | Required |
|----------------------------|------------|---------------------------------------------------------------------------------------------------------------------------------|---------|----------|
| `auto_update_setup_actors` | `boolean`  | Enables updates to `performance_schema.setup_actors` settings. You must also enable `allow_update_performance_schema_settings`. | `false` | no       |
| `collect_interval`         | `duration` | How frequently to check if `setup_actors` are configured correctly.                                                             | `"1h"`  | no       |

### `health_check`

Expand table

| Name               | Type       | Description                          | Default | Required |
|--------------------|------------|--------------------------------------|---------|----------|
| `collect_interval` | `duration` | How frequently to run health checks. | `"1h"`  | no       |

### `prometheus_exporter`

The `prometheus_exporter` block configures the embedded mysqld\_exporter scrapers. The `data_source_name` is inherited from the parent block.

Refer to [`prometheus.exporter.mysql`](../../prometheus/prometheus.exporter.mysql/) docs for the full list of supported arguments and sub-blocks.

## Example

Alloy ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```alloy
database_observability.mysql "orders_db" {
  data_source_name = "user:pass@tcp(mysql:3306)/"
  forward_to       = [loki.relabel.orders_db.receiver]
  targets          = prometheus.exporter.mysql.orders_db.targets

  enable_collectors = ["query_samples", "explain_plans"]

  cloud_provider {
    aws {
      arn = "your-rds-db-arn"
    }
  }
}

prometheus.exporter.mysql "orders_db" {
  data_source_name  = "user:pass@tcp(mysql:3306)/"
  enable_collectors = ["perf_schema.eventsstatements"]
}

loki.relabel "orders_db" {
  forward_to = [loki.write.logs_service.receiver]
  rule {
    target_label = "job"
    replacement  = "integrations/db-o11y"
  }
  rule {
    target_label = "instance"
    replacement  = "orders_db"
  }
}

discovery.relabel "orders_db" {
  targets = database_observability.mysql.orders_db.targets

  rule {
    target_label = "job"
    replacement  = "integrations/db-o11y"
  }
  rule {
    target_label = "instance"
    replacement  = "orders_db"
  }
}

prometheus.scrape "orders_db" {
  targets    = discovery.relabel.orders_db.targets
  job_name   = "integrations/db-o11y"
  forward_to = [prometheus.remote_write.metrics_service.receiver]
}

prometheus.remote_write "metrics_service" {
  endpoint {
    url = sys.env("<GRAFANA_CLOUD_HOSTED_METRICS_URL>")
    basic_auth {
      username = sys.env("<GRAFANA_CLOUD_HOSTED_METRICS_ID>")
      password = sys.env("<GRAFANA_CLOUD_RW_API_KEY>")
    }
  }
}

loki.write "logs_service" {
  endpoint {
    url = sys.env("<GRAFANA_CLOUD_HOSTED_LOGS_URL>")
    basic_auth {
      username = sys.env("<GRAFANA_CLOUD_HOSTED_LOGS_ID>")
      password = sys.env("<GRAFANA_CLOUD_RW_API_KEY>")
    }
  }
}
```

Replace the following:

- *`<GRAFANA_CLOUD_HOSTED_METRICS_URL>`* : The URL for your Grafana Cloud hosted metrics.
- *`<GRAFANA_CLOUD_HOSTED_METRICS_ID>`* : The user ID for your Grafana Cloud hosted metrics.
- *`<GRAFANA_CLOUD_RW_API_KEY>`* : Your Grafana Cloud API key.
- *`<GRAFANA_CLOUD_HOSTED_LOGS_URL>`* : The URL for your Grafana Cloud hosted logs.
- *`<GRAFANA_CLOUD_HOSTED_LOGS_ID>`* : The user ID for your Grafana Cloud hosted logs.

## Compatible components

`database_observability.mysql` can accept arguments from the following components:

- Components that export [Targets](../../../compatibility/#targets-exporters)
- Components that export [Loki `LogsReceiver`](../../../compatibility/#loki-logsreceiver-exporters)

`database_observability.mysql` has exports that can be consumed by the following components:

- Components that consume [Targets](../../../compatibility/#targets-consumers)

> Note
> 
> Connecting some components may not be sensible or components may require further configuration to make the connection work correctly. Refer to the linked documentation for more details.