---
title: Connect to a PostgreSQL database with Cloudflare Workers · Cloudflare Workers docs
description: In this tutorial, you will learn how to create a Cloudflare Workers application and connect it to a PostgreSQL database using TCP Sockets and Hyperdrive. The Workers application you create in this tutorial will interact with a product database inside of PostgreSQL.
lastUpdated: 2025-04-08T01:03:45.000Z
source_url:
  html: https://77261bbd.preview.developers.cloudflare.com/workers/tutorials/postgres/index.md
  md: https://77261bbd.preview.developers.cloudflare.com/workers/tutorials/postgres/
---

In this tutorial, you will learn how to create a Cloudflare Workers application and connect it to a PostgreSQL database using [TCP Sockets](https://developers.cloudflare.com/workers/runtime-apis/tcp-sockets/) and [Hyperdrive](https://developers.cloudflare.com/hyperdrive/). The Workers application you create in this tutorial will interact with a product database inside of PostgreSQL.

## Prerequisites

To continue:

1. Sign up for a [Cloudflare account](https://dash.cloudflare.com/sign-up/workers-and-pages) if you have not already.
2. Install [`npm`](https://docs.npmjs.com/getting-started).
3. Install [`Node.js`](https://nodejs.org/en/). Use a Node version manager like [Volta](https://volta.sh/) or [nvm](https://github.com/nvm-sh/nvm) to avoid permission issues and change Node.js versions. [Wrangler](https://developers.cloudflare.com/workers/wrangler/install-and-update/) requires a Node version of `16.17.0` or later.
4. Make sure you have access to a PostgreSQL database.

## 1. Create a Worker application

First, use the [`create-cloudflare` CLI](https://github.com/cloudflare/workers-sdk/tree/main/packages/create-cloudflare) to create a new Worker application. To do this, open a terminal window and run the following command:

* npm

  ```sh
  npm create cloudflare@latest -- postgres-tutorial
  ```

* pnpm

  ```sh
  pnpm create cloudflare@latest postgres-tutorial
  ```

* yarn

  ```sh
  yarn create cloudflare postgres-tutorial
  ```

This will prompt you to install the [`create-cloudflare`](https://www.npmjs.com/package/create-cloudflare) package and lead you through a setup wizard.

For setup, select the following options:

* For *What would you like to start with?*, choose `Hello World Starter`.
* For *Which template would you like to use?*, choose `Worker only`.
* For *Which language do you want to use?*, choose `TypeScript`.
* For *Do you want to use git for version control?*, choose `Yes`.
* For *Do you want to deploy your application?*, choose `No` (we will be making some changes before deploying).

If you choose to deploy, you will be asked to authenticate (if not logged in already), and your project will be deployed. If you deploy, you can still modify your Worker code and deploy again at the end of this tutorial.

Now, move into the newly created directory:

```sh
cd postgres-tutorial
```

### Enable Node.js compatibility

[Node.js compatibility](https://developers.cloudflare.com/workers/runtime-apis/nodejs/) is required for database drivers, including Postgres.js, and needs to be configured for your Workers project.

To enable both built-in runtime APIs and polyfills for your Worker or Pages project, add the [`nodejs_compat`](https://developers.cloudflare.com/workers/configuration/compatibility-flags/#nodejs-compatibility-flag) [compatibility flag](https://developers.cloudflare.com/workers/configuration/compatibility-flags/#nodejs-compatibility-flag) to your [Wrangler configuration file](https://developers.cloudflare.com/workers/wrangler/configuration/), and set your compatibility date to September 23rd, 2024 or later. This will enable [Node.js compatibility](https://developers.cloudflare.com/workers/runtime-apis/nodejs/) for your Workers project.

* wrangler.jsonc

  ```jsonc
  {
    "compatibility_flags": [
      "nodejs_compat"
    ],
    "compatibility_date": "2024-09-23"
  }
  ```

* wrangler.toml

  ```toml
  compatibility_flags = [ "nodejs_compat" ]
  compatibility_date = "2024-09-23"
  ```

## 2. Add the PostgreSQL connection library

To connect to a PostgreSQL database, you will need the `postgres` library. In your Worker application directory, run the following command to install the library:

```sh
npm install postgres
```

Make sure you are using `postgres` (`Postgres.js`) version `3.4.4` or higher. `Postgres.js` is compatible with both Pages and Workers.

## 3. Configure the connection to the PostgreSQL database

Choose one of the two methods to connect to your PostgreSQL database:

1. [Use a connection string](#use-a-connection-string).
2. [Set explicit parameters](#set-explicit-parameters).

### Use a connection string

A connection string contains all the information needed to connect to a database. It is a URL that contains the following information:

```plaintext
postgresql://username:password@host:port/database
```

Replace `username`, `password`, `host`, `port`, and `database` with the appropriate values for your PostgreSQL database.

Set your connection string as a [secret](https://developers.cloudflare.com/workers/configuration/secrets/) so that it is not stored as plain text. Use [`wrangler secret put`](https://developers.cloudflare.com/workers/wrangler/commands/#secret) with the example variable name `DB_URL`:

```sh
npx wrangler secret put DB_URL
```

```sh
➜  wrangler secret put DB_URL
-------------------------------------------------------
? Enter a secret value: › ********************
✨ Success! Uploaded secret DB_URL
```

Set your `DB_URL` secret locally in a `.dev.vars` file as documented in [Local Development with Secrets](https://developers.cloudflare.com/workers/configuration/secrets/).

```toml
DB_URL="<ENTER YOUR POSTGRESQL CONNECTION STRING>"
```

### Set explicit parameters

Configure each database parameter as an [environment variable](https://developers.cloudflare.com/workers/configuration/environment-variables/) via the [Cloudflare dashboard](https://developers.cloudflare.com/workers/configuration/environment-variables/#add-environment-variables-via-the-dashboard) or in your Wrangler file. Refer to an example of aWrangler file configuration:

* wrangler.jsonc

  ```jsonc
  {
    "vars": {
      "DB_USERNAME": "postgres",
      "DB_HOST": "ep-aged-sound-175961.us-east-2.aws.neon.tech",
      "DB_PORT": "5432",
      "DB_NAME": "productsdb"
    }
  }
  ```

* wrangler.toml

  ```toml
  [vars]
  DB_USERNAME = "postgres"
  # Set your password by creating a secret so it is not stored as plain text
  DB_HOST = "ep-aged-sound-175961.us-east-2.aws.neon.tech"
  DB_PORT = "5432"
  DB_NAME = "productsdb"
  ```

To set your password as a [secret](https://developers.cloudflare.com/workers/configuration/secrets/) so that it is not stored as plain text, use [`wrangler secret put`](https://developers.cloudflare.com/workers/wrangler/commands/#secret). `DB_PASSWORD` is an example variable name for this secret to be accessed in your Worker:

```sh
npx wrangler secret put DB_PASSWORD
```

```sh
-------------------------------------------------------
? Enter a secret value: › ********************
✨ Success! Uploaded secret DB_PASSWORD
```

## 4. Connect to the PostgreSQL database in the Worker

Open your Worker's main file (for example, `worker.ts`) and import the `Client` class from the `pg` library:

```typescript
import postgres from "postgres";
```

In the `fetch` event handler, connect to the PostgreSQL database using your chosen method, either the connection string or the explicit parameters.

### Use a connection string

```typescript
const sql = postgres(env.DB_URL);
```

### Set explicit parameters

```typescript
const sql = postgres({
  username: env.DB_USERNAME,
  password: env.DB_PASSWORD,
  host: env.DB_HOST,
  port: env.DB_PORT,
  database: env.DB_NAME,
});
```

## 5. Interact with the products database

To demonstrate how to interact with the products database, you will fetch data from the `products` table by querying the table when a request is received.

Note

If you are following along in your own PostgreSQL instance, set up the `products` using the following SQL `CREATE TABLE` statement. This statement defines the columns and their respective data types for the `products` table:

```sql
CREATE TABLE products (
  id SERIAL PRIMARY KEY,
  name VARCHAR(255) NOT NULL,
  description TEXT,
  price DECIMAL(10, 2) NOT NULL
);
```

Replace the existing code in your `worker.ts` file with the following code:

```typescript
import postgres from "postgres";


export default {
  async fetch(request, env, ctx): Promise<Response> {
    const sql = postgres(env.DB_URL, {
      // Workers limit the number of concurrent external connections, so be sure to limit
      // the size of the local connection pool that postgres.js may establish.
      max: 5,


      // If you are using array types in your Postgres schema, it is necessary to fetch
      // type information to correctly de/serialize them. However, if you are not using
      // those, disabling this will save you an extra round-trip every time you connect.
      fetch_types: false,
    });


    // Query the products table
    const result = await sql`SELECT * FROM products;`;


    // Return the result as JSON
    const resp = new Response(JSON.stringify(result), {
      headers: { "Content-Type": "application/json" },
    });


    return resp;
  },
} satisfies ExportedHandler<Env>;
```

This code establishes a connection to the PostgreSQL database within your Worker application and queries the `products` table, returning the results as a JSON response.

## 6. Deploy your Worker

Run the following command to deploy your Worker:

```sh
npx wrangler deploy
```

Your application is now live and accessible at `<YOUR_WORKER>.<YOUR_SUBDOMAIN>.workers.dev`.

After deploying, you can interact with your PostgreSQL products database using your Cloudflare Worker. Whenever a request is made to your Worker's URL, it will fetch data from the `products` table and return it as a JSON response. You can modify the query as needed to retrieve the desired data from your products database.

## 7. Insert a new row into the products database

To insert a new row into the `products` table, create a new API endpoint in your Worker that handles a `POST` request. When a `POST` request is received with a JSON payload, the Worker will insert a new row into the `products` table with the provided data.

Assume the `products` table has the following columns: `id`, `name`, `description`, and `price`.

Add the following code snippet inside the `fetch` event handler in your `worker.ts` file, before the existing query code:

```typescript
import postgres from "postgres";


export default {
  async fetch(request, env, ctx): Promise<Response> {
    const sql = postgres(env.DB_URL);


    const url = new URL(request.url);
    if (request.method === "POST" && url.pathname === "/products") {
      // Parse the request's JSON payload
      const productData = await request.json();


      // Insert the new product into the database
      const values = {
        name: productData.name,
        description: productData.description,
        price: productData.price,
      };
      const insertResult = await sql`
        INSERT INTO products ${sql(values)}
        RETURNING *
      `;


      // Return the inserted row as JSON
      const insertResp = new Response(JSON.stringify(insertResult), {
        headers: { "Content-Type": "application/json" },
      });


      // Clean up the client
      return insertResp;
    }


    // Query the products table
    const result = await sql`SELECT * FROM products;`;


    // Return the result as JSON
    const resp = new Response(JSON.stringify(result), {
      headers: { "Content-Type": "application/json" },
    });


    return resp;
  },
} satisfies ExportedHandler<Env>;
```

This code snippet does the following:

1. Checks if the request is a `POST` request and the URL path is `/products`.
2. Parses the JSON payload from the request.
3. Constructs an `INSERT` SQL query using the provided product data.
4. Executes the query, inserting the new row into the `products` table.
5. Returns the inserted row as a JSON response.

Now, when you send a `POST` request to your Worker's URL with the `/products` path and a JSON payload, the Worker will insert a new row into the `products` table with the provided data. When a request to `/` is made, the Worker will return all products in the database.

After making these changes, deploy the Worker again by running:

```sh
npx wrangler deploy
```

You can now use your Cloudflare Worker to insert new rows into the `products` table. To test this functionality, send a `POST` request to your Worker's URL with the `/products` path, along with a JSON payload containing the new product data:

```json
{
  "name": "Sample Product",
  "description": "This is a sample product",
  "price": 19.99
}
```

You have successfully created a Cloudflare Worker that connects to a PostgreSQL database and handles fetching data and inserting new rows into a products table.

## 8. Use Hyperdrive to accelerate queries

Create a Hyperdrive configuration using the connection string for your PostgreSQL database.

```bash
npx wrangler hyperdrive create <NAME_OF_HYPERDRIVE_CONFIG> --connection-string="postgres://user:password@HOSTNAME_OR_IP_ADDRESS:PORT/database_name"
```

This command outputs the Hyperdrive configuration `id` that will be used for your Hyperdrive [binding](https://developers.cloudflare.com/workers/runtime-apis/bindings/). Set up your binding by specifying the `id` in the Wrangler file.

* wrangler.jsonc

  ```jsonc
  {
    "name": "hyperdrive-example",
    "main": "src/index.ts",
    "compatibility_date": "2024-08-21",
    "compatibility_flags": [
      "nodejs_compat"
    ],
    "hyperdrive": [
      {
        "binding": "HYPERDRIVE",
        "id": "<ID OF THE CREATED HYPERDRIVE CONFIGURATION>"
      }
    ]
  }
  ```

* wrangler.toml

  ```toml
  name = "hyperdrive-example"
  main = "src/index.ts"
  compatibility_date = "2024-08-21"
  compatibility_flags = ["nodejs_compat"]


  # Pasted from the output of `wrangler hyperdrive create <NAME_OF_HYPERDRIVE_CONFIG> --connection-string=[...]` above.
  [[hyperdrive]]
  binding = "HYPERDRIVE"
  id = "<ID OF THE CREATED HYPERDRIVE CONFIGURATION>"
  ```

Create the types for your Hyperdrive binding using the following command:

```bash
npx wrangler types
```

Replace your existing connection string in your Worker code with the Hyperdrive connection string.

```js
export default {
  async fetch(request, env, ctx): Promise<Response> {
    const sql = postgres(env.HYPERDRIVE.connectionString)


    const url = new URL(request.url);


    //rest of the routes and database queries
  },
} satisfies ExportedHandler<Env>;
```

## 9. Redeploy your Worker

Run the following command to deploy your Worker:

```sh
npx wrangler deploy
```

Your Worker application is now live and accessible at `<YOUR_WORKER>.<YOUR_SUBDOMAIN>.workers.dev`, using Hyperdrive. Hyperdrive accelerates database queries by pooling your connections and caching your requests across the globe.

## Next steps

To build more with databases and Workers, refer to [Tutorials](https://developers.cloudflare.com/workers/tutorials) and explore the [Databases documentation](https://developers.cloudflare.com/workers/databases).

If you have any questions, need assistance, or would like to share your project, join the Cloudflare Developer community on [Discord](https://discord.cloudflare.com) to connect with fellow developers and the Cloudflare team.
