Skip to content

Latest commit

 

History

History
372 lines (260 loc) · 14.9 KB

README.md

File metadata and controls

372 lines (260 loc) · 14.9 KB

Connecting to TiDB with ORM framework Prisma

Language Driver

The following guide will show you how to connect to the TiDB cluster with Node.js ORM framework Prisma and perform basic SQL operations like create, read, update, and delete.

💡 Tips:

TiDB is a MySQL-compatible database, which means you can connect to a TiDB cluster in your application using the familiar driver/ORM framework from the MySQL ecosystem.

The only difference is that if you connect to a TiDB Serverless cluster with public endpoint, you MUST enable TLS connection on Prisma.

Prerequisites

To complete this guide, you need:

  • Node.js >= 16.x installed on your machine
  • Git installed on your machine
  • A TiDB cluster running

If you don't have a TiDB cluster yet, please create one with one of the following methods:

  1. (Recommend) Start up a TiDB Serverless cluster instantly with a few clicks on TiDB Cloud.
  2. Start up a TiDB Playground cluster with TiUP CLI on your local machine.

Getting started

This section demonstrates how to run the sample application code and connect to TiDB with Node.js ORM framework Prisma.

1. Clone the repository

Run the following command to clone the sample code locally:

git clone https://github.com/tidb-samples/tidb-nodejs-prisma-quickstart.git
cd tidb-nodejs-prisma-quickstart

2. Install dependencies

Run the following command to install the dependencies (including the prisma package) required by the sample code:

npm install
Install dependencies to existing project

For your existing project, run the following command to install the packages:

  • prisma: The ORM framework for Node.js and TypeScript.
  • typescript: The TypeScript compiler.
  • ts-node: The TypeScript execution engine and REPL for Node.js.
  • @types/node: The TypeScript type definitions for Node.js.
npm install prisma typescript ts-node @types/node --save-dev

3. Obtain connection parameters

(Option 1) TiDB Serverless

You can obtain the database connection parameters on TiDB Cloud's Web Console through the following steps:

  1. Navigate to the Clusters page, and then click the name of your target cluster to go to its overview page.

  2. Click Connect in the upper-right corner.

  3. In the connection dialog, select General from the Connect With dropdown and keep the default setting of the Endpoint Type as Public.

  4. If you have not set a password yet, click Create password to generate a random password.

  5. Copy the connection parameters shown on the code block.

    The connection dialog of TiDB Serverless
    The connection dialog of TiDB Serverless
(Option 2) TiDB Dedicated

You can obtain the database connection parameters on TiDB Cloud's Web Console through the following steps:

  1. Navigate to the Clusters page, and then click the name of your target cluster to go to its overview page.

  2. Click Connect in the upper-right corner. A connection dialog is displayed.

  3. Create a traffic filter for the cluster.

    1. Click Allow Access from Anywhere to add a new CIDR address rule to allow clients from any IP address to access.
    2. Click Create Filter to confirm the changes.
  4. Under Step 2: Download TiDB cluster CA in the dialog, click Download TiDB cluster CA for TLS connection to TiDB clusters.

  5. Under Step 3: Connect with a SQL client in the dialog, select General from the Connect With dropdown and select Public from the Endpoint Type dropdown.

  6. Copy the connection parameters shown on the code block.

(Option 3) TiDB Self-Hosted

Prepare the following connection parameters for your cluster:

  • host: The IP address or domain name where the TiDB cluster running (For example: 127.0.0.1).
  • port: The port on which your database server is running (Default: 4000).
  • user: The name of your database user (Default: root).
  • password: The password of your database user (No password for TiDB Playground by default).

4. Set up the environment variables

In the prisma/schema.prisma configuration file, we use the mysql database connector as the provider, and the environment variable DATABASE_URL as the url of the data source.

generator client {
  provider = "prisma-client-js"
}

datasource db {
  provider = "mysql"
  url      = env("DATABASE_URL")
}

Prisma supports loads environment variables from the .env file. Please follow the following steps to set up the DATABASE_URL environment variable:

(Option 1) TiDB Serverless
  1. Make a copy of the .env.example file to the .env file.
  2. Edit the .env file, and replace the placeholders for <host>, <user>, and <password> with the copied connection parameters.
  3. Add the sslaccept=strict parameter to the end of the DATABASE_URL value. (Required for public endpoint)
DATABASE_URL=mysql://<user>:<password>@<host>:4000/test?sslaccept=strict
(Option 2) TiDB Dedicated
  1. Make a copy of the .env.example file to the .env file.
  2. Edit the .env file, and replace the placeholders for <host>, <user>, and <password> with the copied connection parameters.
  3. Add ?sslaccept=strict&sslcert=/path/to/ca.pem to the end of the DATABASE_URL value to enable TLS connections with specified CA certificate, which is downloaded in the previous step. (Recommend for public endpoint)
DATABASE_URL=mysql://<user>:<password>@<host>:4000/test?sslaccept=strict&sslcert=/path/to/ca.pem
(Option 3) TiDB Self-Hosted
  1. Make a copy of the .env.example file to the .env file.
  2. Edit the .env file, and replace the placeholders for <host>, <user>, and <password> with the copied connection parameters.

Skip the below steps if your cluster doesn't enable TLS connections, the TiDB Self-Hosted cluster using non-encrypted connection between TiDB's server and clients by default.

  1. Add ?sslaccept=strict&sslcert=/path/to/ca.pem to the end of the DATABASE_URL value to enable TLS connections with specified CA certificate, which is defined with ssl-ca option.
DATABASE_URL=mysql://<user>:<password>@<host>:4000/test

For more information, please check the documentation of Prisma MySQL connector.

5. Create the database schema

Run following command to invoke Prisma Migrate to initialize the database with the data models defined in prisma/prisma.schema.

npx prisma migrate dev
Data models defined in prisma.schema
// Define a Player model, which represents the `players` table in the database.
model Player {
  id        Int      @id @default(autoincrement())
  name      String   @unique(map: "uk_player_on_name") @db.VarChar(50)
  coins     Decimal  @default(0)
  goods     Int      @default(0)
  createdAt DateTime @default(now()) @map("created_at")
  profile   Profile?

  @@map("players")
}

// Define a Profile model, which represents the `profiles` table in the database.
model Profile {
  playerId  Int    @id @map("player_id")
  biography String @db.Text

  // Define a 1:1 relation between the `Player` and `Profile` models with Foreign Key constraints.
  player    Player @relation(fields: [playerId], references: [id], onDelete: Cascade, onUpdate: NoAction, map: "fk_profile_on_player_id")

  @@map("profiles")
}

To learn how to define data models in Prisma, please check the Data model documentation.

Expected execution output:

Your database is now in sync with your schema.

✔ Generated Prisma Client (5.1.1 | library) to ./node_modules/@prisma/client in 54ms

This command will also generate Prisma Client for TiDB database accessing based on the prisma/prisma.schema.

6. Run the sample code

Run the following command to execute the sample code:

npm start

Main steps in the sample code

The sample code imports the auto-generated @prisma/client package and create a new PrismaClient instance, and then perform some basic CRUD operations in type-safe way.

// Step 1. Import the `@prisma/client` package, which is generated by `npx prisma generate` command.
import {Player, PrismaClient} from '@prisma/client';

async function main(): Promise<void> {
  // Step 2. Create a new `PrismaClient` instance.
  const prisma = new PrismaClient();
  try {

    // Step 3. Perform some CRUD operations with Prisma Client ...
    
  } finally {
    // Step 4. Disconnect Prisma Client.
    await prisma.$disconnect();
  }
}

void main();

Expected execution output:

If the connection is successful, the terminal will output the version of the TiDB cluster as follows:

🔌 Connected to TiDB cluster! (TiDB version: 5.7.25-TiDB-v6.6.0-serverless)
🆕 Created a new player with ID 1.
ℹ️ Got Player 1: Player { id: 1, coins: 100, goods: 100 }
🔢 Added 50 coins and 50 goods to player 1, now player 1 has 150 coins and 150 goods.
🚮 Player 1 has been deleted.

Example codes

Insert data

The following query creates a single Player record, and returns the created player object, which contains the id field that is automatically generated by TiDB:

const player: Player = await prisma.player.create({
    data: {
        name: 'Alice',
        coins: 100,
        goods: 200,
        createdAt: new Date(),
    }
});

For more information, refer to the Create section of CRUD chapter in Prisma Client documentation.

Query data

The following query returns a single Player object with ID 101 or null if no record is found:

const player: Player | null = prisma.player.findUnique({
    where: {
        id: 101,
    }
});

For more information, refer to the Read section of CRUD chapter in Prisma Client documentation.

Update data

The following query adds 50 coins and 50 goods to the Player with ID 101:

await prisma.player.update({
    where: {
        id: 101,
    },
    data: {
        coins: {
            increment: 50,
        },
        goods: {
            increment: 50,
        },
    }
});

For more information, refer to the Update section of CRUD chapter in Prisma Client documentation.

Delete data

The following query deletes the Player with ID 101:

await prisma.player.delete({
    where: {
        id: 101,
    }
});

For more information, refer to the Delete section of CRUD chapter in Prisma Client documentation.

Execute raw queries

The following query executes a raw SQL query and returns the version of the TiDB cluster:

const rows = await prisma.$queryRaw<{ version: string }[]>`SELECT version() AS version;`;
return rows[0].version;

For more information, refer to the Raw database access chapter in Prisma Client documentation.

Best practices

Foreign Key Constraints vs Prisma Relation Mode

For TiDB v6.6.0 or later, it's recommended that using Foreign Key Constraints instead of Prisma Relation Mode for referential integrity checking.

Relation Mode is the emulation of referential integrity in Prisma Client side. The feature may have some performance implications for the application as it requires additional database queries to maintain referential integrity.

Notice:

Foreign keys are suitable for small and medium-volumes data scenarios. Using foreign keys in large data volumes might lead to serious performance issues and could have unpredictable effects on the system. If you plan to use foreign keys, conduct thorough validation first and use them with caution.

What's next