node-postgres pool and query telemetry

Test the integration

Send and verify events with node-postgres pool and query telemetry

Use node-postgres pool and query telemetry where your app knows the final result. Collect only the fields you need, then verify a test event before building charts.

1
Choose the outcome
Postgres connection-pool monitoring
2
Define the contract
query_fingerprint, service, database_name, status, and duration_ms
3
Log the final result
Pass an approved operation fingerprint from the call site instead of deriving it from raw SQL.
4
Check the stored event
Exercise a known fixture, then inspect database_query_completed for one correctly typed terminal row.

Before you start

The pg package with a shared Pool
Application-owned operation fingerprints
A server-side TELEMETRY_API_KEY

Delivery setup

Install and initialize server-side

Import telemetry-sh in server-only code and initialize it once with process.env.TELEMETRY_API_KEY. Keep ingestion credentials out of browser bundles, client-visible environment variables, source control, logs, and exception messages.

node-postgres-install

npm installation

bash

npm install telemetry-sh

1Create one reusable server-side client. Set its timeout and retry limit.
2Log an event when the operation succeeds, fails, retries, or times out.
3Send test events with known results and inspect the stored rows before enabling an alert.

Snippet

Start with one structured event

Add this shape where the workflow completes, fails, or retries. Then build the dashboard from real fields.

node-postgres

node-postgres pool and query telemetry event

javascript

import { Pool } from "pg";
import telemetry from "telemetry-sh";

const pool = new Pool({ max: 10 });
const SAFE_DATABASE_ERROR_CODES = new Set(["40001", "40P01", "55P03", "57014"]);

function classifyDatabaseError(error) {
  return error && typeof error === "object" &&
    "code" in error &&
    SAFE_DATABASE_ERROR_CODES.has(String(error.code))
    ? String(error.code)
    : "database_error";
}

async function runDatabaseOperation({
  queryFingerprint,
  text,
  values,
}) {
  const acquireStartedAt = performance.now();
  let client;

  try {
    client = await pool.connect();
    const acquisitionWaitMs = performance.now() - acquireStartedAt;
    const queryStartedAt = performance.now();
    const result = await client.query(text, values);
    await telemetry.log("database_query_completed", {
      query_fingerprint: queryFingerprint,
      service: "checkout-api",
      database_name: "app_production",
      status: "success",
      duration_ms: Math.round(performance.now() - queryStartedAt),
      acquisition_wait_ms: Math.round(acquisitionWaitMs),
      rows_returned: result.rowCount ?? result.rows.length,
      active_connections: pool.totalCount - pool.idleCount,
      idle_connections: pool.idleCount,
      max_connections: pool.options.max ?? 10,
      waiting_count: pool.waitingCount,
      release: process.env.APP_RELEASE,
      environment: process.env.NODE_ENV,
    });
    return result;
  } catch (error) {
    await telemetry.log("database_query_completed", {
      query_fingerprint: queryFingerprint,
      service: "checkout-api",
      database_name: "app_production",
      status: "failed",
      duration_ms: Math.round(performance.now() - acquireStartedAt),
      error_type: classifyDatabaseError(error),
      active_connections: pool.totalCount - pool.idleCount,
      idle_connections: pool.idleCount,
      max_connections: pool.options.max ?? 10,
      waiting_count: pool.waitingCount,
      release: process.env.APP_RELEASE,
      environment: process.env.NODE_ENV,
    });
    throw error;
  } finally {
    client?.release();
  }
}

Event schema

query_fingerprint, service, database_name, status, and duration_ms

active_connections, idle_connections, max_connections, and waiting_count

acquisition_wait_ms, rows_returned, error_type, release, and environment

Check your setup

Checkpoint 1

Pass an approved operation fingerprint from the call site instead of deriving it from raw SQL.

Checkpoint 2

Measure connection acquisition separately from query execution so pool contention is not mistaken for database work.

Checkpoint 3

Record driver error codes through an allowlist and never forward connection strings, query parameters, or raw database messages.

Verification

Prove the event arrived

Run this after exercising known success and failure cases. Replace the fallback table name if your final event contract differs from the snippet.

node-postgres-verification

node-postgres pool and query telemetry verification query

sql

SELECT *
FROM database_query_completed
ORDER BY timestamp_utc DESC
LIMIT 20;

Confirm one terminal row per logical outcome, with the expected status, identifiers, units, and UTC time.

Inspect the inferred schema and verify that retries do not change field types or generate a new logical event ID.

Search the stored fields for credentials, raw payloads, prompts, private content, and unbounded error messages.

Exercise a provider timeout, ingestion rejection, and process shutdown before treating the dashboard as complete.

Implementation references

Review the event contract, data-safety guidance, and upstream primary documentation before enabling a new production path.

Connection-pool saturation SQL Slow-query fingerprint SQL Database reliability guide Official node-postgres Pool API

Where to log

Keep the outcome event small and recoverable

This pattern provides

Record the outcome as an event you can query with SQL.
Stable fields for dashboards, alerts, and cross-event correlation.
Test events for checking success, failure, retries, and timeouts.

This pattern does not provide

An OTLP exporter, automatic collection pipeline, or replacement for detailed traces and diagnostic logs.
Exactly-once delivery merely because the payload contains an event ID.
Permission to collect raw provider payloads, user content, credentials, or regulated data.

Delivery and idempotency Batching and shutdown Troubleshoot ingestion

Example event schemas

Check what each event records, when to send it, and which field types it needs. Review the example payload and privacy checklist before using it in production.

Database reliability9 fields