使用 Drizzle 和 Vercel Postgres 开始

基本文件结构

这是项目的基本文件结构。在 src/db 目录中，我们在 schema.ts 中有表定义。在 drizzle 文件夹中，有 SQL 迁移文件和快照。

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

第一步 - 安装必需的包

npm i drizzle-orm @vercel/postgres dotenv
npm i -D drizzle-kit tsx

yarn add drizzle-orm @vercel/postgres dotenv
yarn add -D drizzle-kit tsx

pnpm add drizzle-orm @vercel/postgres dotenv
pnpm add -D drizzle-kit tsx

bun add drizzle-orm @vercel/postgres dotenv
bun add -D drizzle-kit tsx

第二步 - 设置连接变量

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

POSTGRES_URL=

第三步 - 将 Drizzle ORM 连接到数据库

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

import { drizzle } from 'drizzle-orm/vercel-postgres';

const db = drizzle();

If you need to provide your existing driver:

import { sql } from '@vercel/postgres';
import { drizzle } from 'drizzle-orm/vercel-postgres';

const db = drizzle({ client: sql })

第四步 - 创建一个表

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

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(),
});

第五步 - 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:

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

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

第六步 - 将更改应用到数据库

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.

npx drizzle-kit generate

npx drizzle-kit migrate

第七步 - 填充并查询数据库

import 'dotenv/config';
import { eq } from 'drizzle-orm';
import { drizzle } from 'drizzle-orm/vercel-postgres';
import { usersTable } from './db/schema';

async function main() {
  const db = drizzle();

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

  await db.insert(usersTable).values(user);
  console.log('新用户已创建！')

  const users = await db.select().from(usersTable);
  console.log('从数据库获取所有用户: ', 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('用户信息已更新！')

  await db.delete(usersTable).where(eq(usersTable.email, user.email));
  console.log('用户已删除！')
}

main();

第八步 - 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

npx tsx src/index.ts

yarn tsx src/index.ts

pnpm tsx src/index.ts

bun tsx src/index.ts

bun src/index.ts