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Get Started with Drizzle and Gel in existing project

This guide assumes familiarity with:

Drizzle has native support for Gel connections with the gel client.

This is the basic file structure of the project. In the src directory, we have table definition in index.ts. In drizzle folder there are generated Gel to Drizzle schema

πŸ“¦ <project root>
 β”œ πŸ“‚ drizzle
 β”œ πŸ“‚ dbschema
 β”‚ β”œ πŸ“‚ migrations
 β”‚ β”œ πŸ“œ default.esdl
 β”‚ β”” πŸ“œ scoping.esdl
 β”œ πŸ“‚ src
 β”‚ β”” πŸ“œ index.ts
 β”œ πŸ“œ drizzle.config.ts
 β”œ πŸ“œ edgedb.toml
 β”œ πŸ“œ package.json
 β”” πŸ“œ tsconfig.json

Step 1 - Install required packages

npm i drizzle-orm gel
npm i -D drizzle-kit tsx
yarn add drizzle-orm gel
yarn add -D drizzle-kit tsx
pnpm add drizzle-orm gel
pnpm add -D drizzle-kit tsx
bun add drizzle-orm gel
bun add -D drizzle-kit tsx

Step 2 - Setup Drizzle config file

Drizzle config - a configuration file that is used by Drizzle Kit and contains all the information about your database connection, migration folder and schema files.

Create a drizzle.config.ts file in the root of your project and add the following content:

import { defineConfig } from 'drizzle-kit';

export default defineConfig({
  dialect: 'gel',
});

Step 3 - Pull Gel types to Drizzle schema

Pull your database schema:

npx drizzle-kit pull
yarn drizzle-kit pull
pnpm drizzle-kit pull
bunx drizzle-kit pull

Here is an example of the generated schema.ts file:

import { gelTable, uniqueIndex, uuid, smallint, text } from "drizzle-orm/gel-core"
import { sql } from "drizzle-orm"

export const users = gelTable("users", {
	id: uuid().default(sql`uuid_generate_v4()`).primaryKey().notNull(),
	age: smallint(),
	email: text().notNull(),
	name: text(),
}, (table) => [
	uniqueIndex("a8c6061c-f37f-11ef-9249-0d78f6c1807b;schemaconstr").using("btree", table.id.asc().nullsLast().op("uuid_ops")),
]);

Step 4 - Connect Drizzle ORM to the database

Create a index.ts file in the src directory and initialize the connection:

import { drizzle } from "drizzle-orm/gel";
import { createClient } from "gel";

const gelClient = createClient();
const db = drizzle({ client: gelClient });

Step 5 - Query the database

import { eq } from "drizzle-orm";
import { drizzle } from "drizzle-orm/gel";
import { createClient } from "gel";
import { users } from "../drizzle/schema";

const gelClient = createClient();
const db = drizzle({ client: gelClient });

async function main() {
  const user: typeof users.$inferInsert = {
    name: "John",
    age: 30,
    email: "john@example.com",
  };

  await db.insert(users).values(user);
  console.log("New user created!");

  const usersResponse = await db.select().from(users);
  console.log("Getting all users from the database: ", usersResponse);
  /*
  const users: {
    id: number;
    name: string;
    age: number;
    email: string;
  }[]
  */

  await db
    .update(users)
    .set({
      age: 31,
    })
    .where(eq(users.email, user.email));
  console.log("User info updated!");

  await db.delete(users).where(eq(users.email, user.email));
  console.log("User deleted!");
}

main();

Step 6 - Run index.ts file

To run any TypeScript files, you have several options, but let’s stick with one: using tsx

You’ve already installed tsx, so we can run our queries now

Run index.ts script

npx tsx src/index.ts
yarn tsx src/index.ts
pnpm tsx src/index.ts
bunx tsx src/index.ts

tips

We suggest using bun to run TypeScript files. With bun, such scripts can be executed without issues or additional settings, regardless of whether your project is configured with CommonJS (CJS), ECMAScript Modules (ESM), or any other module format. To run a script with bun, use the following command:

bun src/index.ts

If you don’t have bun installed, check the Bun installation docs