开始使用 Drizzle 和 Neon

This guide assumes familiarity with:

Drizzle 原生支持与 neon-httpneon-websockets 驱动程序的 Neon 连接。这些操作在底层使用了 neon-serverless 驱动程序。

使用 neon-httpneon-websockets 驱动程序,你可以通过 HTTP 或 WebSockets(而非 TCP)从无服务器环境访问 Neon 数据库。对于单个非交互式事务,通过 HTTP 查询速度更快。

如果你需要会话或交互式事务支持,或者需要完全兼容 pg 驱动程序的嵌入式替代品,你可以使用基于 WebSocket 的 neon-serverless 驱动程序。你可以使用 Postgres 直接连接到 Neon 数据库

Basic file structure

This is the basic file structure of the project. In the src/db directory, we have table definition in schema.ts. In drizzle folder there are sql migration file and snapshots.

📦 <project root>
 ├ 📂 drizzle
 ├ 📂 src
 │   ├ 📂 db
 │   │  └ 📜 schema.ts
 │   └ 📜 index.ts
 ├ 📜 .env
 ├ 📜 drizzle.config.ts
 ├ 📜 package.json
 └ 📜 tsconfig.json

步骤 1 - 安装 @neondatabase/serverless 包

npm
yarn
pnpm
bun
npm i drizzle-orm @neondatabase/serverless dotenv
npm i -D drizzle-kit tsx

步骤 2 - 设置连接变量

Create a .env file in the root of your project and add your database connection variable:

DATABASE_URL=

步骤 3 - 将 Drizzle ORM 连接到数据库

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

import { drizzle } from 'drizzle-orm/neon-http';

const db = drizzle(process.env.DATABASE_URL);

If you need a synchronous connection, you can use our additional connection API, where you specify a driver connection and pass it to the Drizzle instance.

import { neon } from '@neondatabase/serverless';
import { drizzle } from 'drizzle-orm/neon-http';

const sql = neon(process.env.DATABASE_URL!);
const db = drizzle({ client: sql });

步骤 4 - 创建表

Create a schema.ts file in the src/db directory and declare your table:

src/db/schema.ts
import { integer, pgTable, varchar } from "drizzle-orm/pg-core";

export const usersTable = pgTable("users", {
  id: integer().primaryKey().generatedAlwaysAsIdentity(),
  name: varchar({ length: 255 }).notNull(),
  age: integer().notNull(),
  email: varchar({ length: 255 }).notNull().unique(),
});

步骤 5 - 设置 Drizzle 配置文件

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:

drizzle.config.ts
import 'dotenv/config';
import { defineConfig } from 'drizzle-kit';

export default defineConfig({
  out: './drizzle',
  schema: './src/db/schema.ts',
  dialect: 'postgresql',
  dbCredentials: {
    url: process.env.DATABASE_URL!,
  },
});

步骤 6 - 应用更改到数据库

You can directly apply changes to your database using the drizzle-kit push command. This is a convenient method for quickly testing new schema designs or modifications in a local development environment, allowing for rapid iterations without the need to manage migration files:

npx drizzle-kit push

Read more about the push command in documentation.

Tips

Alternatively, you can generate migrations using the drizzle-kit generate command and then apply them using the drizzle-kit migrate command:

Generate migrations:

npx drizzle-kit generate

Apply migrations:

npx drizzle-kit migrate

Read more about migration process in documentation.

步骤 7 - 种子和查询数据库

Let’s update the src/index.ts file with queries to create, read, update, and delete users

src/index.ts
import 'dotenv/config';
import { drizzle } from 'drizzle-orm/neon-http';
import { eq } from 'drizzle-orm';
import { usersTable } from './db/schema';
  
const db = drizzle(process.env.DATABASE_URL!);

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

  await db.insert(usersTable).values(user);
  console.log('New user created!')

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

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

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

main();

步骤 8 - 运行 index.ts 文件

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

npm
yarn
pnpm
bun
npx 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