The Custom Metrics section appears on the database instance detail page and displays timeseries graphs for any custom queries you have defined in your Datadog Agent configuration.

Overview

If you have configured custom_queries in your Datadog Agent’s database integration, this section automatically discovers those queries and visualizes each metric column as a timeseries graph. This lets you monitor business-specific or environment-specific database metrics alongside the standard Database Monitoring metrics, all in one place.

How it works

1. Define custom queries in your Agent config. Each query specifies:

• A SQL statement
• One or more metric columns (with types like gauge, count, or rate)
• Optional tag columns
• An optional metric prefix
• An optional collection interval

2. The Agent collects the metrics by running your SQL queries on the configured interval (default: every 15 seconds) and emitting the results as Datadog metrics.
3. The Custom Metrics section displays a graph for each metric column from your custom queries, scoped to the current database instance. Metrics are named <prefix>.<column_name> (for example, postgresql.my_table_row_count).

Example Agent configuration

The following PostgreSQL example tracks table size and row counts per table:

init_config:

instances:
  - dbm: true
    host: localhost
    port: 5432
    username: datadog
    password: <PASSWORD>
    custom_queries:
      - metric_prefix: postgresql.custom
        query: |
          SELECT
            table_name,
            pg_total_relation_size(quote_ident(table_name)) AS total_bytes,
            n_live_tup                                       AS live_rows,
            n_dead_tup                                       AS dead_rows
          FROM information_schema.tables
          JOIN pg_stat_user_tables USING (table_name)
          WHERE table_schema = 'public'
        columns:
          - name: table_name
            type: tag
          - name: total_bytes
            type: gauge
          - name: live_rows
            type: gauge
          - name: dead_rows
            type: gauge
        collection_interval: 60
        tags:
          - env:production
          - service:my-app

This configuration produces three metrics, each broken down by table_name:

• postgresql.custom.total_bytes
• postgresql.custom.live_rows
• postgresql.custom.dead_rows

All three appear as separate timeseries graphs in the Custom Metrics section of the instance detail page.

Column types

Each column in a custom query is assigned a type that controls how the metric is aggregated and displayed:

count and monotonic_count columns are aggregated as sum. All other metric types are aggregated as avg.

Viewing the source SQL

Each graph has a View SQL query button in the top-right corner. Clicking it shows the raw SQL statement that produces the metric, so you can understand and audit what is being measured.

Collection interval

The section subtitle shows how often the metrics are collected (for example, “collected every 15s”). If you have multiple custom queries with different intervals, the range is shown (for example, “collected every 15s–60s”).

Requirements

Custom queries must be defined under the custom_queries key in the database integration configuration. The Custom Metrics section is hidden if no custom queries are configured.

Further Reading

Additional helpful documentation, links, and articles:

Collecting Custom Metrics with Database MonitoringDOCUMENTATION Database MonitoringDOCUMENTATION