How to Fix DatabaseError in TypeScript

Nothing disrupts a coding session quite like an unexpected DatabaseError in TypeScript. Here's how to diagnose and fix it.

Root Cause

A DatabaseError typically means your application can't communicate with the database. Common causes include incorrect connection strings, connection pool exhaustion, missing migrations, or network issues between your app and the database server.

Step-by-Step Fix

The key is to configure connection pooling and timeouts in your TypeORM data source:

import { DataSource } from "typeorm";

export const AppDataSource = new DataSource({
  type: "postgres",
  url: process.env.DATABASE_URL,
  synchronize: false,
  logging: ["error", "warn"],
  extra: {
    max: 10,
    connectionTimeoutMillis: 5000,
  },
});

await AppDataSource.initialize();
console.log("Database connected");

Common Pitfall

Before diving into code changes, double-check your environment variables and TypeScript version. Version mismatches between local and deployed environments are a frequent source of this error. While you're at it, check if your logging captures enough context around this error to speed up debugging next time.

Validate the Solution

Verify by triggering the same action that caused the original error. In TypeScript, you can also enable verbose logging temporarily to confirm the fix is applied correctly. Once verified, remove or reduce the logging level to keep your logs clean in production.

Stay Ahead of Errors

To prevent this from recurring unnoticed, set up [Bugsly](https://bugsly.dev) for your TypeScript project — it monitors errors and gives you actionable alerts.