MySQL

Source URL: https://docs.prisma.io/docs/orm/core-concepts/supported-databases/mysql

MySQL

Use Prisma ORM with MySQL databases including self-hosted MySQL/MariaDB and serverless PlanetScale

Prisma ORM supports MySQL and MariaDB databases, including self-hosted servers and serverless PlanetScale.

Setup

Configure the MySQL provider in your Prisma schema:

schema.prisma

    datasource db {
      provider = "mysql"
    }

Self-hosted MySQL/MariaDB:

prisma.config.ts

    import { defineConfig, env } from "prisma/config";

    export default defineConfig({
      schema: "prisma/schema.prisma",
      datasource: {
        url: env("DATABASE_URL"), // mysql://user:pass@host:3306/db
      },
    });

PlanetScale:

prisma.config.ts

    import { defineConfig, env } from "prisma/config";

    export default defineConfig({
      schema: "prisma/schema.prisma",
      datasource: {
        url: env("DATABASE_URL"), // Uses connection string from PlanetScale
      },
    });

Using driver adapters

Use JavaScript database drivers via driver adapters:

Withmariadb driver:

npm

pnpm

yarn

bun

    npm install @prisma/adapter-mariadb

    import { PrismaMariaDb } from "@prisma/adapter-mariadb";
    import { PrismaClient } from "./generated/prisma";

    const adapter = new PrismaMariaDb({
      host: "localhost",
      port: 3306,
      connectionLimit: 5,
    });
    const prisma = new PrismaClient({ adapter });

PlanetScale serverless:

npm

pnpm

yarn

bun

    npm install @prisma/adapter-planetscale undici

    import { PrismaPlanetScale } from "@prisma/adapter-planetscale";
    import { PrismaClient } from "./generated/prisma";
    import { fetch as undiciFetch } from "undici"; // Only for Node.js <18

    const adapter = new PrismaPlanetScale({
      url: process.env.DATABASE_URL,
      fetch: undiciFetch,
    });
    const prisma = new PrismaClient({ adapter });

Supported variants

• Self-hosted MySQL/MariaDB

Standard MySQL (5.6+) or MariaDB (10.0+) servers.

• Connection URL: mysql://user:pass@host:3306/database
• Full Prisma Migrate support
• Use prisma migrate dev for development
• Both MySQL and MariaDB use the same mysql provider

Connection string arguments:

Argument	Default	Description
connect_timeout	5	Seconds to wait for connection
sslcert		Path to server certificate
sslidentity		Path to PKCS12 certificate
sslaccept	accept_invalid_certs	Certificate validation mode

• PlanetScale

Serverless MySQL-compatible database built on Vitess clustering system.

• Connection URL: Update host to aws.connect.psdb.cloud
• Uses Vitess for horizontal scaling
• Database branching workflow (development/production branches)
• Non-blocking schema changes

Key features:

• Enterprise scalability across multiple servers
• Database branches for schema testing
• Non-blocking schema deployments
• Serverless-optimized (avoids connection limits)

Branch workflow:

1. Development branches - Test schema changes freely
2. Production branches - Protected, require deploy requests
3. Deploy requests - Merge dev changes to production

Schema changes:

Use prisma db push (not prisma migrate):

npm

pnpm

yarn

bun

    npx prisma db push

PlanetScale generates its own schema diff when merging branches.

Referential integrity options:

Option 1: Emulate relations (recommended for default PlanetScale)

Set relationMode = "prisma" to handle relations in Prisma Client:

schema.prisma

    datasource db {
      provider     = "mysql"
      relationMode = "prisma"
    }

Add indexes on foreign keys manually:

    model Post {
      id       Int       @id @default(autoincrement())
      title    String
      comments Comment[]
    }

    model Comment {
      id     Int    @id @default(autoincrement())
      postId Int
      post   Post   @relation(fields: [postId], references: [id])

      @@index([postId]) // Required when using relationMode = "prisma"
    }

Option 2: Enable foreign key constraints

Enable foreign key constraints in PlanetScale settings to use standard relations without relationMode = "prisma".

Resources: PlanetScale docs • Prisma integration

Type mappings

• Type mapping between MySQL and Prisma schema

Prisma	MySQL/MariaDB
String	VARCHAR(191)
Boolean	TINYINT(1)
Int	INT
BigInt	BIGINT
Float	DOUBLE
Decimal	DECIMAL(65,30)
DateTime	DATETIME(3)
Json	JSON
Bytes	LONGBLOB

See full type mapping reference for complete details.

Common patterns

SSL connections:

    DATABASE_URL="mysql://user:pass@host:3306/db?sslcert=./cert.pem&sslaccept=strict"

Unix socket connections:

    DATABASE_URL="mysql://user:pass@localhost/db?socket=/var/run/mysqld/mysqld.sock"

PlanetScale sharding (Preview):

Define shard keys in your schema:

    generator client {
      provider        = "prisma-client"
      output          = "./generated/prisma"
      previewFeatures = ["shardKeys"]
    }

    model User {
      id     String @default(uuid())
      region String @shardKey
    }

Connection troubleshooting:

PlanetScale production branches are read-only for direct DDL. If you get error P3022, ensure you’re:

• Using prisma db push instead of prisma migrate
• Working on a development branch, or
• Using a deploy request to update production