Query D1 from Remix

Remix is a full-stack web framework that operates on both client and server. You can query your D1 database(s) from Remix using Remix's data loading ↗ API with the useLoaderData ↗ hook.

To set up a new Remix site on Cloudflare Pages that can query D1:

Refer to the Remix guide.
Bind a D1 database to your Pages Function.
Pass the --d1 BINDING_NAME=DATABASE_ID flag to wrangler dev when developing locally. BINDING_NAME should match what call in your code, and DATABASE_ID should match the database_id defined in your Wrangler configuration file: for example, --d1 DB=xxxx-xxxx-xxxx-xxxx-xxxx.

The following example shows you how to define a Remix loader ↗ that has a binding to a D1 database.

Bindings are passed through on the context.cloudflare.env parameter passed to a LoaderFunction.
If you configured a binding named DB, then you would access D1 Workers Binding API methods via context.cloudflare.env.DB.

import type { LoaderFunction } from "@remix-run/cloudflare";
import { json } from "@remix-run/cloudflare";
import { useLoaderData } from "@remix-run/react";

interface Env {
  DB: D1Database;
}

export const loader: LoaderFunction = async ({ context, params }) => {
  let env = context.cloudflare.env as Env;

  try {
    let { results } = await env.DB.prepare("SELECT * FROM users LIMIT 5").run();
    return json(results);
  } catch (error) {
    return json({ error: "Failed to fetch users" }, { status: 500 });
  }
};

export default function Index() {
  const results = useLoaderData<typeof loader>();
  return (
    <div style={{ fontFamily: "system-ui, sans-serif", lineHeight: "1.8" }}>
      <h1>Welcome to Remix</h1>
      <div>
        A value from D1:
        <pre>{JSON.stringify(results)}</pre>
      </div>
    </div>
  );
}